@Guspaz I'd rather the mc be the one to vanish. He's not that bad of a character, but going by what's happening here he's definitely deserves some sort of punishment here.
@HerculeSSJ "I thought I was gonna like that goddess character when I first saw her. Now I'm hoping she bites the dust."
For what, for doing what's best for her territory? If you knew there was a great chance your country would be razed by the enemy because an incompetent person was put into power, would you really do nothing, and just wait and see?
His life is no longer only his, him staying an incompetent will also bring doom to Rin. Of course things will benefit the MC in the long run because the MC is the MC and this is fiction.
However, thinking realistically. The MC really is the one at fault here.
Sure he lost his past memeories, but he was given a chance to return to form and he has refused that. Ignorance is no excuse when you have the opportunity to gain knowledge.
The punishment is too harsh for the crime, yes, but if he loses he'd be crippling Rin for life. Not only that he'd invite disaster to his town and hundreds would lose their lives just because he wanted to avoid trouble.