It could be mental thing for him? Or just the Warriors are getting old? They still have a lot of role players just like when they have those incredible runs as a champion. But it seems that Kerr and his system are no longer working for them and yeah, Curry and Draymond are in the mid 30's already and so their game might be regressing, specially Draymond.
He's stats is promising on their first 5 game early this season that's why many people think about that he's a big deal in the roster and people feel like Warriors made a good decision to get him then let go of Klay in their roster. But unfortunately now he's inconsistent and performance is declining. See his stats here https://www.statmuse.com/nba/ask/buddy-hield-stats-when-starting
Maybe he's just pressured on the expectation he got from fans that's why he's afraid to commit a mistake because he will be highlighted on news with these situation. But hopefully next year Hield and Warriors could sort out the issue and they could able to start strong then could able to maintain their momentum. Their system is overused and many teams already know how to counter it so maybe they should think about other thing since adjustment is important to win their games.
We're expecting a change in their momentum. I believe the team can make some recovery. They did this before, and there's no reason they can't adjust. But for Hield, he should adapt to the situation he has now and never think about the pressure. If he wants to grow, then he must show his real talent.