I've been using the Beta version of Photostructure[0] for a while and am generally very happy with it.
It doesn't have all the bells and whistles, no ML etc, but it's also much lighter. Running on my Synology NAS inside a docker container just fine (with ~30k photos).
I also heard about Mylio[1] which looks nice, but haven't tried it. Somehow the privacy policy left me a little more concerned compared to the bold promises elsewhere. The pricing model also feels a bit off to me.
Neither are open-source though.