Sure, run a homelab as a hobby. Everybody has hobbies.
Once your user count goes beyond 1, you suddenly have a SLA as people are dependent on your services. Like it or not, you are now the primary support staff of your local cloud business.
The more users you get, the more time you will need to spend to fix problems.
At which point does it go from a hobby to a 2nd job ?
You're still arguing from the point of view of someone who doesn't want to do it or isn't interested in doing it. Your GP said you 'get' homelabs but it's increasingly clear you do not - and that's ok. People run homelabs because they enjoy learning and tinkering. If they don't enjoy it, or they can't risk having the odd problem, they have other options they can explore. It's not really any more complicated than that. Believe it or not, people are capable of evaluating the tradeoffs and making a sensible decision about what to host themselves.