"Notice: due to the recent influx of traffic, new subscriptions are closed." https://masto.host/
"hi! there's been a huge wave of new members and new instances recently, and that's a Lot of work.
i am tired and especially won't be very available in the next months for health reasons, so i won't be accepting new instances for a while." https://fedi.monster/
A lot of users on these are opening up public instances, rather than their own. I don't see a huge amount of "host mastodon for yourself on your own domain" people.
"hi! there's been a huge wave of new members and new instances recently, and that's a Lot of work. i am tired and especially won't be very available in the next months for health reasons, so i won't be accepting new instances for a while." https://fedi.monster/
"Due to overwhelming demand, registrations are currently closed." https://cloudplane.org/