His shot selection is usually bad / he shoots too much, which means he shouldn't be allowed to do what, say, Kyrie does. If he was a decent shooter, this would be ok.
Apart from in the clutch he is a very bad shooter, so he should not be taking shots very early in the shot clock because we can almost certainly get an equal or better look from a much better shooter. He also dribbles around and puts up shots as the clock expires that are bad shots, though I don't fault him when he gets passed the ball with like 2-3 seconds on the shot clock.
The worst is his guaranteed heat check 3 point attempt after he makes a 3, which has maybe gone in once in his entire career. That's a Jamal Crawford shot and he shoots like the opposite of Jamal Crawford.
The complaints are 100% legitimate. I have nothing against Smart, I'd love him to shoot less or improve his shot because then I'd probably be happy to pay him unless it costs us Rozier.