The only solution I've been able to use is removing the SD card we use in our Moto G6 phones for extra storage of photos. The Photos app seemed to freeze once it tried to read past around 2000 photos, and we had at least 10 GB worth on the SD card. Removing it made the app just search for photos in internal storage, and it worked fine.
I will note that it had previously been able to scan the sd card just fine, but now won't. I suspect it's because the volume is too late.
Anyway, maybe this can help others.