What do you see that makes you think Deni has a quick 1st step? Most of his movement towards the basketball is with the help of a pick. He’s going to struggle to create on his own in the NBA. I don’t see a lot of functional athleticism.
I've seen some evidence on his live games. Just two samples:
From 7:12', against Yves Pons who is considered a great defender and an elite athlete:https://youtu.be/CtBkxDY1ZJI?t=431
From 1:36, 1 v1 against John Holland, who is a good athlete:
Remember he's a 6'9-6'10 who is still grow into his body, don't expect him to show a 6'5 like first step.
Which means he’ll be a poor shooter
Your statement was based off the idea he has a bad first step, which I don't think it's correct. Also, you a bit overrating the first step thing, most of the times you see a wing beat a defender 1v1 is thx to a screen, or due to his ball handling and ability to recognize the right moment to attack. Obviously the first step is a good advantage, but not the only one.
,struggle to create outside of the pick and roll,
According to his scouting report his PnR skills ranks in the 92nd percentile (1.054 PTS/POS)
and I don’t think defense is going to be his calling card.
Probably not his calling card but also not a liability. He will have a good combination of big body, good enough lateral movement and good positioning to not be a liability on defense, mixing it with some weak side shot blocking, deflections/steals and high level team defense.
We are going to look back in 3 years at all the warning signs and wonder how everyone didn’t see it. He’s Gallinari without the elite shooting.
The lazy become lazier. Except they're both white European 6'10 players, they are not the same. Here is what Tyler Metcalf who has a nice draft site and spent hundreds of hours on evaluating each prospect in this class has to say about it: