> because I don't want to be Oncall 24/7/365

Yes I don't recommend doing that. My experience is that people understand you are human because they know you. They don't expect 9 9s availability but if they somehow do that can be clarified from the start : "I'm hosting this free of charge for family members because (insert your reasons here, it's important to clarify WHY it's different because Apple and BigTech in general somehow still have a ton of goodwill) but as you know as also have a job and our family life. Consequently sometimes, e.g. electricity outage or me having to update the server, there will be down time. Do no panic when this happens as the files are always safe (backup details if you want) but please do be patient. Typically it might take (insert your realistic expectation, do NOT be too optimistic) a day per month for updates. If you do have better solutions please do contribute."

... or something of the kind. I've been doing that for years and people are surprisingly understanding. IMHO it stems from the why.

The "way cheaper than the equivalent" argument reminds me of, and apologies I know it's a bit rough, Russian foreign minister days ago who criticize the EU for its plan to decouple with their oil & gas saying something like "Well if they do that they will pay a lot more elsewhere" and he's right. The point isn't the money though, the point is agency and sovereignty.