Wait for a fix.
Currently, CPU defenders aren't bumping into screens (at least for me). They are just sliding around them while not changing their animation from the defensive stance. Seems like a bug. This is only happening to defenders defending me and not the CPU. Auto layup choices are also way off. My guy keeps going to revers clutch layups when a simply left hand finger roll will do the trick. However, that is easily fixed with using the RS.
I, like you, also cannot take even late contested shots. Maybe badges will fix this but unless my defender is miles away from me, it is considered a "bad shot". I play on HOF and am still shooting around 40-50%, but it is getting to me a little. I set a screen or run my plays (I usually run plays every time up the floor), my defender runs right into the screen but acts like it's not even there. I isolate a little and create a nice opening for a shot and it's considered a D grade. Yet, the CPU can set a screen and take a short step back to land a nice three behind the screen. I really like this because it's super realistic, but for some reason when I take the shot, defenders that are not right in my face are still considered as being such.
I liked it better in 2K15 where the defender had to be right on you or you had to be right on the shooter for it to be contested. Much more realistic. However, it does seem like a bug because the CPU is able to pull it off. We usually get a patch soon after release that fixes little things like this.
Don't get me wrong, I LOVE what they did with on ball defense this year. Finally, my player is assisted in grabbing who he's defending even as a low rated player and I feel like I am doing well on defense. But offense needs major tweaking. It feels realistic in terms of the way the defender moves, but they have way too much room for error at the moment.