
Comparisons between 19-20 and 2021-22
Defense
Opponent FT/FGA is 18th this season and was 16th in 19-20
Opponent eFG% is 8th this season and was 7th in 19-20
Opponent TOV% is 3rd this season and was 11th in 19-20
Lakers DRB% is 7th this season and was 24th in 19-20
Offense
Lakers FT/FGA is 18th this season and was 16th in 19-20
Lakers eFG% is 9th this season and was 5th in 19-20
Lakers TOV% is 27th this season and was 23rd in 19-20
Lakers ORB% is 26th this season and was 4th in 19-20
Lakers appear to be impacting shots as well as ever but are slightly worse from the field. Lakers are getting less turnovers and are turning over the ball slightly more. This is getting them less possessions per game.
The real story appears to be rebounding. Their drop in DRB% and ORB% from 19-20 to 21-22 is staggering.
One aspect that might be contributing is the average height of the Lakers on the floor this season:
Player size : Lakers average player height is 23rd this season and was 4th in 19-20
Beyond the height aspect I think effort on boxing out has been critical here. Impact rebounding stats (RAPM-based stats) look at the impact of a player on rebounding differentials when they are on the court. It isn't just thinking about who gets the rebound but it also includes boxing out technique.
Howard and McGee were a big part of the rebounding impact in 2019-20. Caruso, Green were excellent impact rebounders for perimeter guys, KCP and Kuzma were decent.
Howard has been poor comparatively, Lakes lost a lot of the guys above and they really didn't bring in any impact rebounders in the offseason.
Westbrook is one of the worst impact rebounders in the league but by looking at box stats you might see him as a decent rebounder. Steven Adams and Capela are probably the best impact rebounders in the game and both helped to hide Westbrooks flaws on teams in the past. In reality, Westbrook picks off easy rebounds and doesn't box out well.
TLDR - I think main struggles are due to not thinking about rebounding when making offseason moves and perhaps naively assuming that Westbrook could help carry the rebounding burden with AD at the C. Generally rebounding is a team effort play and effort is something the Lakers can improve in the playoffs but I think they really should look to trade for an impact rebounder or two. Also, less forced turnovers of opponents is likely due to the loss of KCP and Caruso, that is not something that is likely to get back.