My completely unnecessary two cents is that Hussie & co. were/are planning on releasing an official HS collection, or otherwise becoming the main source again... which, yknow, is fair. It is their creative work after all.
So they tried to get the UHC either taken down or merged with the new OHC. One way or another, the discussions went pretty bad -- given Hussie's track record, I don't doubt that at least some of Gio's claims are true, but I doubt he had no part in things going sour.
Re: the question of "why would Gio lie", the blog post (on Vriska day, of all days) and the text recreations instead of screenshots is pretty obviously his attempt to get ahead of the narrative. He's accepted that he's probably not gonna be able to outright save the UHC, and that it's gonna become public eventually, so he presented the story in the light most favourable to himself. Probably also why he used text recreations so much -- to leave out any parts that make him look bad, even if his claims are still generally true.
Alary has a very good point, too -- it was honestly kind of discomforting seeing him use he/him exclusively in the post. I didn't catch that he even changed quotes. That doesn't mean he's lying about Hussie's behaviour, but it does mean he's kind of a dick himself, and probably writing as much out of personal distaste as he is from any nobler intentions.
(its also worth noting how many people in this very forum were also using only he/him in the initial backlash... yikes)
air fryer? um, thats called a Prince of Breath ._.