I've been sold on Tatum for a while. IMO he's the #2 prospect in this draft behind Fultz. He has an advanced offensive game, his FT% gives optimism that he will become a dangerous shooter in time, and he's a much better defender than his reputation (he was a plus defender at Duke; while he lacks Jackson's pure athleticism, he's a good positional defender and he's actually longer than Jackson).
You can question his decision-making and lack of elite athleticism. Those are fair criticisms. Otherwise, I think he checks a ton of boxes in terms of what you look for in a top-of-draft prospect.