Photos albums aren't syncing/updating

[srbNYC]

I backup and sync my iPhone XS directly (wired) with my M1 MBA, and in the Finder, under Photos, I have "All Photos and Albums" set to sync. But when I add photos to an album on my Mac and then sync, most of the time those new photos do not show up in the corresponding albums on my iPhone.

I have restarted both devices, and even ran Repair Library on the Photos app on my MacBook. Had anyone encountered/solved this? Is it a bug, or can I do something to fix it? Thanks.

 

[srbNYC]

Update: Found a workaround (to uncheck "All Photos and Albums" and instead check "All Albums" above the list of albums. It replaced/reloaded all my Mac's photos (which on my M1 MBA was impressively fast).

But that can't be the actual way to regularly and automatically get it to recognize that a photo or two have been added and update appropriately. "Sync" means sync, right?