It's the timing that ultimately got me. It's genuinely insulting taking the context of the moment. That and the fact the ending just makes everything you do pointless. It makes you feel like playing through the game was a waste of time. The second ending makes you feel that at least this happened for SOMETHING.
I think that may be why I want caught as much off guard as a lot of others were and could just sit back and bask in its absurdity. And I'm completely done with the game now (aside from trying out the stuff coming in the season pass wacky DLC packs) so it was a nice way to put a hard stop to my wanting to go back and play around in Hope County any time soon.
I totally understand WHY so many people didn't like that ending though.