Deserved, imo. Not surprising people are disappointed if you act like you're able to create Disney level animations and shitting on other developers work in the process before even having finished a single animation. But hey, he can blame his "special dev" now. lol
And some guys here will still white knight him no matter what, saying we are toxic or whatever. Sure, there are trolls and toxic pplz here, but there are also non-pledgers fans who stay objective/quiet BUT still get upset with the Dev's behavior. Like you said, talking big, shitting on other Dev's Work and bragging on the EXCELLENT QUALITY of his vids triggered some kind of hostility among a category of fans that were not necessarily against him in the first place.
Speed was always the main issue. Few updates and little progression. Had he not bragged about/overhyped his animations that much, pplz wouldn't be that angry/sarcastic. Impatient, sure, but not angry.
Like Gingersweetgirl often said here, he's very bad at communicating. He should recruit someone (a community manager perhaps?) for that purpose. No matter how good of a Dev/Artist he can be, he can't be good in all aspects : Communication/marketing are things that most Devs don't master.