I suspect that Tatum's shot selection is a symptom of a different problem (and no, Kobe is not the problem... that's garbage). My main issue with Tatum right now is that he has a tendency to freeze whenever he receives the ball in the half court. This gives the defense time to adjust. His man catches up, and the off ball defenders shift in his direction. This means he has to deal with a lot more traffic than he otherwise would have when he finally unfreezes. He's more likely to pull up because he thinks he can't get all the way to the rim, and when he does drive he's more prone to getting stripped. Tatum has done this freezing thing since college.
Contrast that to Jaylen Brown. I know a lot of people are out on him right now, but one of the things I like about him is that there's little hesitation in his game. As soon as he gets the ball, he's doing something with it - driving, shooting, or passing. Rarely does he just hold it while he decides what to do next. He doesn't give the defense time to key on him. I think he has quietly adapted his game to an off ball role much better than people realize, but it's masked by a horrific shooting slump that may or may not be a product of his hand injury. I'd like Tatum to adopt Brown's decisiveness into his own game.