Its true that its someone else’s server but in my case I get phone and photo backups for au$25/year (approx. us$16.50 or €15).
I manage servers for a living but for my personal data I am happy to pay a relatively small fee for the convenience of having someone else deal with patching, backups, and hardware lifecycles.
I’m glad there are self hosted solutions but its a bit like home bread baking, an interesting hobby for people who are interested or have unique needs - but there are also serviceable options available for purchase at reasonable prices.