What's the point with that quite lackluster story in Endwalker?

[CrownySuccubus]

Despite my hatred of his character, depending on the dialog options you choose, he does express regret and apologizes for his actions.

When?

The guy literally continues trying to kill you and keeps mocking you about the coming apocalypse right until you kill him as Amon within the goddamn afterlife. Yeah, Amon didn't see himself as Hermes entirely, but he sure as hell saw himself as Hermes when he asked "Was this the answer I was searching for?" In the end, it was still all about himself.

Also, even if Hermes himself was sorry about his actions right at the end, this changes nothing because he still got to live with his erased memories and get everything he wanted.

As far as her being the main antagonist, it's because for all intents and purposes the Final Days was averted. Mankind had passed Hermes' test and were trying to get back to normal.

Not really. If anything, the pre-Sundering cutscene showed that most Ancients had become horribly unhinged by the Final Days. Sacrificing other lives to revive their people aside, they were now twice as determined to live their lives as a paradise, and their disregard for non-Ancient lives was more pronounced than ever.

Doesn't excuse what Venat did, but this "And then all was well" narrative just isn't true.

EDITING to reply to below so I don't use up my daily post allowances:

I think you can also understand how someone who has a history with certain forms of abuse would find Venat's approach to murder far more personally disturbing, and thus prompting more outrage, versus Hermes's. (Not that Hermes wasn't abusive to Meteion. Oh boy, is that a can of worms.)

By the same token, I hope you can understand how someone who has suffered at the hands of privileged idiots who ignored various rules and warnings that are put into place for a reason would not give a damn about how premeditated Hermes' actions were before Ktisis. And then, after Ktisis, how someone who may be the victim of gaslighting, assaulted in a manner that they can't remember said assault, or may have lost loved ones due to one person's selfishness (for example, the millions of people who have died from COVID because of other peoples' stupidity) can see how evil Hermes was.