Is it really worth to kill Demogorgon?

This is another shower thought, is it really worth to kill Demogorgon?

Like, I know when you kill him you sent him back to the abyss (And I'm pretty sure I read somewhere that he can come back anyway) but Watcher's Keep was meant to be his prison

The watchers call you because the ward weakened not because the prison itself isn't strong enough and that lead me think that the "Lawful Good" way to beat watcher's keep is to imprison him there forever instead of giving him another chance to rise even if that takes centuries.

What do you think?