The way I had Photoprism set up is that mine and my wife's phones would sync images nightly to the server, the photos would be rsyncd from the public facing sync server to an internal one (not in the DMZ) then I'd have the server send me a link to the import page on Photoprism because it lacks the feature to autosync when new files are added; I think having to open the page while on LAN (link was internal only) and click a button was the straw that broke the camels back here for me.
I think I also had something like 10-12 cores dedicated to it, which alongside the RAM use that constantly crept up, and the manual intervention, was just too much for a photo management tool that wasn't really even managing the photos in a way that was useful to us.
Multi-user is lacking to missing. I'm not 100% sure which state photoprism is in, as I was shopping for a self host service. OTOH I don't care about that for family. I'm not hosting anything for untrusted people, or to default backup everything, but as common library. So I'm fine if everyone sees everything and expect people to play nice.
But I do agree that multi user (and maybe integrated auto-sync for phones) are major missing features. I'm just in the situation that it doesn't really matter to me currently.