Personally, I think that answer changes a lot depending on how you look at it. There as ways of cutting it that have me put Duncan at the top and ways of cutting it where Kobe is way ahead of him and Tim is closer just above Curry. I tend to think the difference between "greatest" and "best" is a matter of cultural impact beyond talent or accomplishments.
Jordan, deservedly or not, would be the GOAT by that standard, and it would be really close between Kobe and Lebron for second, with perhaps this gold having a chance to seal the debate. Then guys like Curry and Paul George have had such huge cultural impacts on young players that they're much higher on the list than some might believe. Tim was great, but almost by his intention, it's easy to overlook him. That's especially true of his peak, which ended a decade before he retired. People saw Old Tim for so much longer than most players that it made many forget that he had much more dynamism and cache once upon a time.
But if we're only talking about the cultural impact on one organization and what he could do as the centerpiece of a franchise, Tim stands alone in the modern era. Maybe Bill Russell makes an argument for "All-Time", but there's no player in NBA history I'd rather start a franchise with. Not Jordan, not Lebron, not K

be, not even Wemby. It's Tim and there are no other right answers. Because I don't really care about basketball as a cultural or media phenomenon, I'll go with Tim as much overall answer.