The best Spider-man movie to date features Peter losing his powers and giving up on being Spidey entirely. The (debatably) best Superman movie also features him losing his powers. I don’t see your point.
Yes, and he discovers he makes a mistake and get’s his powers back. That’s not the same as permanently altering a character.
In the comics Marvel altered Spider-Man history, by having him make a deal with the Devil, and exchange his marriage for his aunt’s life. This story was the biggest retcon in the comic’s history, and is widely considered one of the worst retcons in comic book history, because it made 20 years of comic history irrelevant to future content.
Change can be both good and bad depending on your point of view. It can even be both, which is probably a good description my perspective on TLJ.