Photos iCloud updating with no visible progress
I am trying to sync my photo databases between my iPhone (running iOS 15.1.1) and two Macs (running MacOS Monterey 12.2.1). On one of my Macs (a new MacBook Pro with M1 Pro), the Photos app seems perpetually "Updating..." and is not reflecting changes on the other two devices even after a week. In fact, the system photo database file does not change in size, which makes it wonder that anything is helping.
For reference, here is what each device shows...
iPhone
- 35,413 Photos
- 3,584 Videos
iMac that says "Updated Just Now"
- 35,334 photos
- 3,571 videos
- 257.65 GB* in the system photos database "Photos Library"
MacBook Pro that seems stuck on "Updating..." (does not mirror iPhone)
- 35,449 photos
- 3,578 videos
- 108.72 GB* in the system photos database "Photos Library.photoslibrary" file
Note: ^^^ these values do not appear to be changing
*both the iMac and MacBook Pro are logged into the same iCloud account and have Photos preferences "Optimize Mac Storage" which makes it very curious the large discrepancy in system photos database files.
I've read through posts stating that, for very large photo databases, "just wait" and so I have. But it's now been at least a week. I've set the MacBook to not sleep and kept it connected to ethernet that is showing about 100 MB/s upload and download speeds. Nothing noticeable changes.
Also for reference: If I take a new picture with my iPhone, it shows up in Photos in the "Updated Just Now" iMac but does not show up in the "Updating" MacBook Pro. That seems fishy.
I have other photos databases I need to import and merge, so the MacBook Pro stuck on "Updating..." is delaying my efforts and is making me wonder if I have a problem that no amount of waiting will solve? If so, are there any other remedies or solutions? I am tempted to delete the database and copy over the one from the iMac, but I fear that the MacBook Pro actually has some photos/videos that the other two devices (or iCloud) has that I could lose if I do that.
Any advice is greatly appreciated!