I tried both ~1,5 years ago, Immich won the "spouse test" as I could get my partner to use the app on her phone (with her own profile) instead of the native gallery.

Photoprism didn't support profiles or have an app (back then at least, don't know about today), and I couldn't convince her of using some other gallery in the browser...

I for myself liked the Photoprism GUI, but I could never get the face recognition to work well, and manually tagging people/places (or basically doing anything) on thousands of pictures was quite painful.