Grayven own the tree so many presents for cutting him that much slack.
I can only speak for myself but for me the issue isn't about consequences or anything like that. The problem is that Grayven is legitimately an arsehole and much of his screen time has been spent deriding characters I like better than him.
Watching him give 'the reason you such' speeches is not endearing. Watching him come to equestria for help, repeatedly make an ass of himself for no reason, then solve the problem with no help from anyone (indeed with having to help Luna merely survive while he is at it) is not endearing.
That said we are only on part 14, I trust that Mr Zoat has something more nuanced in the works that Grayven shouting "See how right I was?!" as the conclusion.
I kinda feel like you missed the part where it's already more nuanced than that. Remember how he's already been called out for being wrong on the details of the Pinkie Clone Murder Spree? Or how his antics have directly led to Luna invading his dreams, leading to Luna's self-inflicted psychic scars feeding the anti-life and helping set it free? Or how all of this is very likely driven by the AL influencing his approach to dealing with them in the first place, inspiring him to desperation and cruelty instead of diplomacy? And that he's an easy target for that
because he's such a hammy jerk to begin with? Which is a huge part of why he has an AL fragment in the first place?
No, his behavior isn't endearing for all that it is sometimes hilarious. This isn't the first time Grayven's propensity for hamatics has bitten him in the ass and it probably won't be the last, but his arcs have basically
always been more nuanced than people who can't read past his bluster credit. Yes, he often comes out the other side right and righteous, but only because he manages to correct his course, one way or another, before it kills him. In the end he is generally at least
less wrong than when he started, but there are a few particular kinds of mistakes he just can't help repeating because they've become baked into his nature because he
started on this path by pretending to be a large ham villain. He made that face so often it stuck.
People don't enjoy Grayven because he's an arrogant jerk, people enjoy Grayven for his sheer dynamism and the fact that he is on every level so much more outwardly energetic than the Paragon. Yes, a certain percentage of that time is inevitably spent watching him sail himself directly into the next catastrophe as hard as possible. Some people even enjoy him for the way he manages to constantly, as he already has in this sequence, to troll both everyone around him
and himself.
The man is a walking petard factory that still manages to get shit done. It's almost like Zoat is channeling the American stereotype version of himself and the contrast with Original Edition is delicious.