He was unprofessional for years, see the firings of 2024
That is really when the sudden shift in his public manner happened. It has been going on that long. He should have stepped back as either Automattic CEO or Wordpress BFDL at least a year ago IMO; the ACF/SCF debacle settled it.
WP and the community around it would have been better for it if he had.
WP was the community's, apparently, not Matt's. Unless it suited him, in which case it was his.
WP was open source, and WP Engine followed the license. What crookery?
Oh, they misrepresented themselves as being WP affiliated, like the claimed "independence" of WP.com (Matt's for profit entity, not the open source app)? Why was one okay not the other?
Let's not discuss that Matt, and Automattic, while pushing press releases saying that WP was forever an unencumbered open source app for the community, that very same day issued WP.com an exclusive, free, unlimited, irrevocable commercial license... didn't tell anyone about that, it came out in the lawsuit.
Or that the WP community board was effectively Matt and a friend, and a largely absent third friend.
Crooks, stealing? WP Engine contributed to the OSS app with thousands of developer hours a year - not as many as Matt "felt" they should. And only them, not other WP hosters.
Crooks, stealing? WP Engine donated six digits a year to sponsor and support WP community events, including the one where Matt went on stage and spent 45 minutes slandering them - after disinviting them, and refusing to return their sponsorship or donation. He made WP Engine effectively pay to give him a stage to talk shit about them.
Crooks, stealing? Like Matt taking software packages that WP Engine wrote, doing a search/replace on Copyright, license, authorship, and replacing their entries (with all their accumulated community reviews, ratings, followership and traction) with his wholesale-copied variants?
Matt was unhinged. I think "right to be" is "debatable, at best".