Camera technology keeps evolving everyday... so some day there probably will be cameras that are so much better than anything we have today, even bringing up the differences we find among the current models will be a worthless thing to talk about. Even on that day, paint-artists will think that they're still superior to photographers lol
I've been using a Sony T7 and I'm currently using a Sony H9. If you think the Sony forum is better, it could be due to the following reasons:
1. Some Sony cameras (like my H9) can be used to take quite impressive shots, fairly easily. Lots of casual photographers use Sony cameras for this reason, and since this is a camera/photography enthusiast forum that comes up very easily on Google, the ones who're conscious and curious about their shots could be posting their best ones here.
2. Some of these cameras (like the H9 and the T7 I've used) have features that can be manually tweaked to get much better results. So, finding the right settings is like an adventure on its own to some of us and we're always exploring how to take better shots, sometimes of the same thing, until we find the camera's absolute limit.
3. Maybe since there's a general notion that other brands are better than Sony, the Sony users who discover the positive things about their cameras try to demonestrate otherwise. And casual photographers who've bought traditionally known brands (e.g. Nikon, Canon, etc.) might be trusting their equipment to take perfect shots every time, they're not interested in others' opinions of their shots or might not feel that they need to prove anything.
So that's what I suspect...
Good question btw!
GTW