I've been using #Immich as my photo backup solution for the past two years, many things have improved, and it is safe to say that it has become the best open source photo backup solution.
Discussion
Have you tried PhotoPrism? Immich had some breaking changes lately, have you been negatively affected by this?
Before Immich I was using Photoprism, but I really think Immich is far superior in many things. Particularly in background phone sync, and overall phone experience.
Breaking changes are usually a few edits to the docker-compose.yml file, and I haven't experienced any issues in this ~2 years by just following the update instructions on the release notes.