it’s all done voluntarily in people’s free time.

Firstly, Matrix has plenty of paid developers that work on it - this is not even close to a passion project made by volunteers in their free time.

Secondly, I'm not saying the work is embarrassing (the work is nothing short of incredible), I'm saying the priority to leave this feature on the backburner for years is. They likely ended up with more important priorities and didn't have enough resources to dedicate, but on a practical level the lack of hotjoin voice channels sticks out like a sore thumb to new users.

I've been championing Matrix for about 4-5 years now, and it's been so long since this feature was requested/promised that it's at the point where I'm too "embarrassed" to try to convince people to switch anymore. People just expect this feature in a messaging platform nowadays, and if it's not there they're going to leave immediately. When this makes it into stable with a good UX, I'll be back on the new user pipeline.