Really ? I have been self hosting for atleast three years.

Dendrite, conduit and synapse - matrix homeserver software (you have to use one of them) have thousands of stars.

I'm pretty sure atleast 10k+ matrix homeserver deployments exist - maybe someone from matrix.org can give a better number because each homeserver is probably federating with theirs.

And thats to say nothing of unfederated servers i.e. orgs hosting matrix for internal use.