Running a Matrix homeserver is still quite a pain in the ass, especially because there is no real automatic way to purge old history. Join a busy room once and pay for it in megs or gigs of text stored in your DB forever.

Just using a matrix.org account instead is antisocial at this point because of the resources you're taking from the project, whereas paying for a hosted homeserver might not be something everyone can afford. IRC instead only requires a bouncer in the worst case, and even if you stay on channels for years you won't accrue as much history as a Matrix room can generate in a few days. I find that easier to maintain and store.

I do run my own Matrix homeserver and I intend to keep doing that and paying for it, but Matrix has more rough edges than IRC at the moment IMHO.

Edit: Ah, sorry, this was actually meant in reply to parent. But gonna leave it in.