Just today I paid for a domain name in name.com. As part of the package, they sold me a hosted & managed WordPress installation for $60 USD a year. I was positively impressed (last time I setup a WP server I paid $5 a month for DigitalOcean, which makes it $60 for something I have to manage).
Companies like name.com, godaddy and whatnot should offer that kind of option. Or even AWS should have a "managed mastodon" server maybe. At the end of the day, most companies nowadays have their infrastructure in one of the 4-6 main cloud providers (AWS, Azure, GCS, Oracle, ...).