My rankings:
1. LeBron James
Spoiler:

It's probably pretty clear that he's the most dominant force of the decade. 8 out of 10 possible finals, leading two different dynasties. 3 rings, 3 MVPs, 3 FMVPs, All-Star and All-NBA every single season, missing First Team All NBA only once, plus 5 All Defense awards.
2. Stephen Curry
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Leading the most dominant dynasty of the decade, and one of the best individual talents. 3 championships, 5 back-to-back finals, and 2 MVPs.
3. Kevin Durant
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Got his championships while joining an already great team, but still was part, you may argue the main part, of an unstoppable force in the league, and even without that - he might have been third in the decade. One of the best scorers in those seasons, and of all time actually, who led OKC to one NBA Finals and three more Conference Finals.
4. Chris Paul
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Lacking any notable playoff success until joining forces with Harden in Houston, but still is one of the best two-way talents of the decade, especially with positional adjustment.
Was the leader of a very good Clippers team that had been consistently one of best regular season teams, and has been an MVP candidate in a decent chunk of those years (third in 12', fourth in 13', seventh in 14' and you may argue made the case for Griffin's third, sixth in 15' and 16'). Also key part of the team that almost knocked Warriors out in 18'.
5. Kawhi Leonard
Spoiler:
Harder to evaluate, as unlike the previous guys - he wasn't playing for the entire decade, and wasn't a star until the middle of it, but was a (super) role player in some of those years. Still, he was a crucial part of the Spurs ring in 14' and is responsible for one of the best carry-jobs in recent years, at the very last year of the decade. MVP candidate from the moment he became a star, and might be the most dominant two-way force of the given timeframe (expect LeBron? Davis?), especially if we're looking on a several years timeframe.
6. James Harden
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Began the decade as a (very good) sixth man, and once he came to Houston - he became one of the primary offensive forces in the league. Very good scoring consistency throughout the decade, very good facilitator and incredible advanced stats. Also had some nice playoff success, including the impressive 18' Conference Finals with Paul.
7. Anthony Davis
Spoiler:

Some might argue it's too high for him. Not too much playoff success, but unlike some of the names ranked after him, he was a consistent performer and one of the top players in the league for a decent chunk of the decade - even though he didn't play all of it. Also I believe had some of the best peak years. Like Kawhi, is a dominant force on both ends of the floor, but I believe didn't have the right supporting personnel in those years, and unfortunley his 20' PS run is excluded here.
8. Tim Duncan
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The Big Fundamental was still a fundemental part of the league in the 10s, although it's obviously only his second best decade. Still, leading Spurs to another ring in 14', plus consistent playoff success in the beginning of the decade - conference finals in 12' and another finals appearance in 13'. The arguments against him are that he was declining in this decade, has only one First Team All NBA (with 2 more Thirds), and was retired by 16'. Though I can see someone putting him higher, or lower. An interesting case.
9. Draymond Green
Spoiler:

The greatest anti-hero of the decade. The heart and engine of the most dominant dynasty of the decade, one of the greatest defenders of all time, and an exceptionally good facilitator for a big man / forward.
10. Dwyane Wade
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Key part of two championship teams, one of the best guards in the league in the beginning of the decade. Could've been a First Teamer in more years in the beginning of the decade (still got one before LeBron joined), but took a co-pilot role alongside LeBron that probably reduced his numbers somewhat. Still put up very good numbers many of those years, but was declining especially by the second half of it.
11. Dirk Nowitzki
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I give a lot of credit here for his fantastic 11' PS run, and he was still a top guy the beginning of the decade with 3 All-NBA (2 Second, 1 Third). Also had some nice impact numbers in many of those years, but was declining and getting too old in the latter part of the decade.
12. Russell Westbrook
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Half of the two-headed monster in OKC alongside Durant. Not a fan of his style of play, nor of his stat-padding years and stat-padded MVP, but it's hard to argue he's one of the most accomplished players in the decade, and a dominant offensive force in his prime.
13. Kobe Bryant

His back-to-back championships for the Lakers are right on the border of this decade and the previous one, with the second championship included in our timeframe. Was still claiming for the spot of the league's alpha dog for almost half a decade, but was aging, and had a drop in 14' with his knee injury - becoming nearly irrelevant later on. Depending on how you weigh in peak years vs longevity, you may rank him higher, and like in Duncan's case - I can also see claims of putting him too high.
14. Dwight Howard
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One of those harder cases to evaluate as he was a still quite dominant force in the beginning of the decade, but started losing relevance by the half of it. Still, was second in MVP votes in 11' and fourth in 10', had a strong PS run in 10' ending up in 7 games in ECF, plus was the second guy on the Houston team that made the WCF in 15'. Also is a strong candidate for the best defensive anchor in the first part of the decade.
15. Paul George
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Another two-way star and impact guy, who accomplished some nice achievements for Indiana in the given decade, and even became a one-time First Team All-NBA by the end of the decade. Very good playoff series against LeBron's Miami in 12', 13' and 14', dragging the Heatles to 6, 7, 6 games respectively.
16. Damian Lillard
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One of the best guard scorers of the decade. He could have been selected to the All-Star a few more times I believe, and was becoming truly great in the latter part of the decade, including a First Team All NBA. Also led Portland to the WCF in 19', and had several nice playoff runs.
17. Giannis Antetokounmpo
Spoiler:

Only played for a little more than half a decade and was becoming a true impact guy only by 17' but had three very good years, including an MVP by the end of the decade, scoring the highest DBPM of the decade (4.1) in 19', plus leading the Bucks to ECF. This is a case of a pretty short prime, and one very good year, so I'm sure some of you will keep him out of the top 20, but decided to put him in anyway.
18. Jimmy Butler
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The most impressive part about Jimmy in this decade is the way he was elevating every team he got to, helping Minny securing their best winning record since KG (and ever since), and a key member in Philly's impressive playoff run in 19', nearly eliminating the eventual champions. Also some nice PS runs in 12' and 15' in Chicago. He became an even more dominant playoff performer in the current decade, but still had a great one in 10s.
19. Marc Gasol
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Anchoring one of the best defenses in the NBA, and very nice playoff performances leading Memphis - in 11' eliminating 1st seeded Spurs and taking OKC to 7 games in Semi WCF, in 13' getting to the WCF eliminating Clippers and OKC on their way, and in 15' getting to the Semi WCF and eliminated by eventual champions GSW in 6 games. The prototype of the modern big man, with 3pt range, great defense, and also very good passing skills. By the end of the decade, he was the starting center of the 19' champions Toronto, playing a key role in this PS run as well.
20. Klay Thompson
Spoiler:

The fact that's he has never had the chance to be the leader of a team is kinda hurting him. Still, he's an essential part of the GSW dynasty, and a very good scorer, with high consistency, and obiously some impressive PS record. His title of being "one of the best shooters of all time" is based almost exclusively on the years in question.
Honorable mentions:
LaMarcus Aldridge, Pau Gasol, Chris Bosh, Kyrie Irving, DeMar Derozan, Kevin Love, Blake Griffin, Tony Parker, Manu Ginobili, Kevin Garnett, Nikola Jokic, Carmelo Anthony, Andre Iguodala, Kyle Lowry, Derrick Rose, Al Horford