The implied refutation of "You don't know what specific requirements people have" is that there will be people with specific requirements that a Pi/Mini PC obviously doesn't meet.
Like what?
Any type of redundancies.. Geo, power, network. There's a million possible reasons why someone can't just deploy on a pi and call it a day.
Do you need that? If a storm knocks my power out for a couple hours and my side project has an outage, that's fine.
This is side project, not typical web project. For a typical web project stability and safety of data are paramount.
I think you mean "critical business" not "typical web project", which is not critical to anything.
Granted, I'm sure the average engineer will be very relieved to find out they're paramount to production.
If you're making money off a project I suspect you're generally too far gone for advice. Then again I suppose you don't need it.