All fair. And I just don't know what was going on under the hood on those teams and agree we probably won't for years. So I'm just guessing on all of this too.
My guess? Durant has been a sneakily bad teammate all along- for all the greatness in his game, the "most flexible player" hype, and media-friendly appearances the fact is he bailed on OKC, bailed on an amazing situation in GS, bailed on the Nets, and has already made noises about bailing on the Suns. He has had mediocre relationships with a bunch of teammates and a bunch of coaches (calling for various others to be fired as he's gone along) and made some odd choices (Kyrie!) as well. The case for him as any sort of leader is literally non-existant---he has never led a team anywhere, and all evidence is he's the greatest number two ever (or maybe co-greatest with Pippen) and unable to be a leader. The case for him as a good teammate boils down to "GS succeded with him for a few years" doesn't it? We only know about 25% of what goes on, and I fully agree with you Draymond driving him away is absolutely on the table. But so is Durant being a selfish ass and Curry or Draymond calling him out on it is my only note there. So, I dunno what to make of that other than agreeing that Kerr definitely failed to solve it!
With the 2016 thing, no dispute why they lost. I have said a few times along the way I think kerr enables Draymond, and that's my best guess. So I tend to land where you do on criticism of that. I do have some doubt there though - I suspect Draymond is a lot closer to Dennis Rodman's personality than most think and so keeping him mostly on-message may be quite an accomplishment. But that's just speculation.
The other point against Kerr is how awful the team was without Curry the one year he missed---it's not a totally fair thing to look at as they decided to tank, but it's a (small) data point against him. But let's also give credit for all the success and championships, even if we give a ton of the credit to Curry Kerr still was there and deserves credit too.