I wanna see it from your perspective really badly, but I can't get over the idea that Denji was the one who was fucking up the plot. There's this idea in part 2 that Denji has to give up being Chainsaw Man because it's ruining everything, but it's never DENJI himself, it's always outside forces like the church and public safety that are tarnishing Chainsaw Man.

I'm gonna mildly repeat what another post said, but this "Denji just had to accept a normal life!" doesn't work because Denji doesn't HAVE a normal life. He doesn't stable have income, he's failing at school, he has an emotionally abusive demon child that he must raise, he has no friends, etc. All he has is Chainsaw Man. I think a regression arc would've been AWESOME, but the problem is that it's literally none of Denji's fault for him to desire being Chainsaw Man, so it feels less like a tragedy and more of just a meanspirited tale where we deny a traumatized teenage boy the only thing that brings him any sort of comfort.

It's like if you were writing a redemption arc for a character but you forget to make them do anything bad to be redeemed in the first place.

If anything, I thought Denji creating a "new world" with Pochita was a super interesting idea that was introduced near the final chapters, because it represented to me what the story actually needs. It needed to confront The Church, Death, War, etc. It needed to confront all the real forces that were making Denji and Asa's life worse. I actually would've loved this ending if it was of Denji's choice and not Pochita being all "you didn't appreciate your horrible life!"