Also interested in this. The ideal solution would stream to a private server for storage in real-time, with access control so you can grant trusted individuals access.
This would allow retention of evidence in a scenario where your phone is seized/destroyed/lost or you are detained, and would give you (and whoever you choose to grant access) the ability to control distribution, unlike a livestream to Twitch or YouTube or whatever.
Matrix is notorious for its poor performance with large/numerous groups. They keep claiming to improve it, but it's still bad.
I mean, it's great that it works for you, but be honest: isn't your tolerance for technological friction a bit higher than the average bear's? People complain that Mastodon is too hard, and Matrix is ten times worse to sign up for and use.
I hate to say it, but Matrix is never going to be mainstream. Its UX is bad and it seems like it's too bloated to fix. If I tried to get people to move from Discord to Matrix, they'd never take me seriously again. It was hard enough getting people to move from Facebook Messenger to Signal.