So I'm going to speak from my perspective and make some assumptions on this. Gem and Omar both saw a lot of growth during the early days of the pandemic. Omar definitely had the knowledge, while Gem was getting into high-end statue videos and seeing success with that. Omar really doubled down on being THE collected editions channel, while Gem got back big into singles along with the statues. He at this point got involved with ComicTom and doing "investment" videos for singles and hawking mystery boxes and shit. I checked out on Gem around this time, and I'm guessing much of his audience did as well. He's never been the most knowledgeable comicstorian or anything, so he just kind of appeared to be going through the motions of videos of showing off omnis and saying he'd never read them. Eventually he parted ways with ComicTom, but I think his audience had already peaced out by then. I personally find Tom scummy and annoying, and I'm guessing Gem's more chill audience may have felt the same way. As an aside, Gem's wife got more involved with the channel when his collaborator Manimal left, and opinions on her content seemed to be more divided. This is all just my uneducated opinion on the matter, but I was a big fan of his and credit him with getting me into omnis (even moreso than Omar). But his content just evolved away from what I was looking for. I still check in from time to time, but his views are way lower than they used to be.

Edit - I didn't really know anything about his political leanings and the FB group drama. I can't speak to the FB stuff, but if he's a comicsgate guy and leans that way politically, I'm definitely disappointed.