Not to be rude, but what explicitly, made him an ass from your perspective?
Look at it from his standpoint. He has an untold amount of people vying for his attention, comments that hopefully are managed by a 3rd party/other folks, and who knows quantity of people contacting him with ideas for a story, video, or some such. I don't even know if he still even runs or manages his repair business at all at this point. When you combine all those things, you end up getting into a mindset of filtering out what matters to you and/or others very quickly and having little time for much else especially if people wax on and are not good at getting to the point.
I get that HN isn't Reddit in the sense that you don't see long form comments like this, but I've dealt with this a lot in the Information Security industry. I think that's what may separate people who get shit done from infosec rockstars and other folks who talk a big talk, but when you get to know them, they are deep down, jerks. I could share my own stories of Deviant Ollam, JohnnyXm4s or other individuals -- but how much of that is my own bias and frustration with what I did, or did not get when interacting with those people? It does not make them assholes just because I did not get the experience I expected.
Years ago, when he was still in NYC, I posted a minor technical correction under one of his videos on reddit and received a rambling essay-length reply plus an aggressive DM from him about how "people like me" are trying to bring him down, all at ~4am his time. That's not "filtering out what matters" it's evidence of paranoid mania, and that's all I see in his videos now.
I'm glad he's been able to turn this into a career doing genuinely good work that I agree with, but he is first and foremost a drama youtuber and that requires a confrontational personality.