I don't understand his free throw form at all. In college he can even shoot 3's.
Why does he not dribble a couple times to get a rhythm?
Why does he stop mid shot and hold the ball up high in a tense position which is only tiring out his arms?
Why does he only shoot with arms and no legs?
If you are doing a bench press, what is easier:
A. Lifting in 1 motion
B. Lifting halfway, holding it for 2-4 seconds and then pushing it out?
Isn't A. obviously easier? He is short on so many free throws because his arms are tense and because he uses no legs. If he would shoot in 1 motion, he wouldn't be so short on so many shots.
The only other issue might be his workout schedule. He needs to give enough recovery time between his arm workouts (bi/tri/etc) before games. Shooting after a tricep workout is like walking with no legs. It's pretty much impossible.
On a side tangent, if I was Ben Simmons shooting coach, I would teach him to work on his free throws 1 handed until he is consistently able to get under the ball and get rid of this side spinning action on the ball