The only thing the Warriors have going for them is money.
What did Durant leave behind with the Warriors with his three straight FMVP titles? The opinion of many fans is to chase more championships and elevate their place in history. That's the right answer. But before adding Durant, the Warriors were the championship team. Durant did well against the Warriors twice in a row, but that didn't erase the opinion of many. Three consecutive three-legged FMVPs would open up two possibilities for him. One would be to eliminate the perception of his opponents (but personally, I don't think that would be difficult). In this case, Durant will be more likely to stay with the Warriors. The other would still not eliminate the opinions of others. And then his remaining championships with the Warriors won't be any more helpful to his style or place in history.
For a specific example we can look at Russell, the Lord of the Rings. In the first game of history, even with the FMVP trophy named after him, Russell couldn't match Jordan. Even in a matchup between the same position, meaning the first center, the first choice of many is not in the playoffs, and he has not won him for Chamberlain many times. There's no reason for that, the Celtics are formidable. So, personally, I don't think more tournaments and FMVPs will do that much for KD unless the Warriors win five in a row and six in a row resulting in a change in numbers. If KD really wants to improve his all-time standing, then winning the Thunder is an option. (But the Thunder have effectively blocked that path.) The other option is to lead a team to the pinnacle of team history, or step back and lead the long-awaited revival of the Giants, like this year's minor label. Adding legend is a great way to improve the theme and the state of history.
If the Warriors don't win three straight titles? If KD is very arrogant, then the team may have to lead the way to another title. But, if you look at it dispassionately, that's no different than winning the Warriors. If he stays with the Warriors to improve his place in history, he'll have to pay more and get more accolades. In the meantime, it will always face skepticism. After all, the Warriors have a great system and coaching, and two top scorers. (One of them remains overwhelming.) Not having three consecutive championships means a lot of things have to build up. It also means more effort.