In the first part of their domination, you could say the Warriors' greatest rival was the Clippers. Their matchups guaranteed tremendous basketball, but it soon became clear the Clips can't hang with the Warriors. Chris Paul always believed he's better than Steph and always lost to him. All that was left to do was to become a gif.
But when all is said and done about the Warriors, their greatest rival will probably be the team Paul joined to try and beat them - the Houston Rockets. (Apart from their usual Finals meeting with LeBron). When everyone decided to wait for the Warriors to age out of their prime, Daryl Morey decided to go all in. And he did it creating a team that's the complete opposite of the Warriors.
Mike D'Antoni, who developed "7 seconds or less" in Phoenix with Steve Kerr as his GM, gave the ball to James Harden and told everyone else to stand in the corner. They won a lot of games and ruined the spirit of basketball. That's what makes a great rivalry - it's not just that there's a great team you are often up against. You have to dislike them.
The fact Steve Kerr said winning against the Rockets in Game 6 in 2019 is his favorite game with the Warriors tells you all you need to know. That's why few were surprised when Kerr answered a question about maybe changing the system of play like this.
Kerr added that the off-ball movement is what makes Steph and Klay special. Draymond playmaking, while the Splash Brothers don't stop moving, is at the core of Warriors basketball. They don't do it just because it wins them games. It's a reflection of their philosophical belief that's how the game is meant to be played. I agree with them.
There is one caveat to next season. The Rockets still don't have a head coach, so we may see a different identity on the court next year, depending on who they hire. This is mostly wishful thinking on my side - it's a players league, and as much as Harden claims he doesn't want to play the way he played the last few seasons, we know that's not true.
Many people are developing theories about the NBA TV ratings being in the tank. I know one thing that will help. A healthy, rested, and hungry Steph, Klay, and Draymond reminding everyone they're not done yet.