Big Sur upgrade changed my Photo files
When I upgraded to Big Sur, my Mac Photo files were changed, and then could only be opened by a computer running Big Sur - Apple should not be allowed to do this, as my 2 other Mac Airs running Catalina could no longer access my Photos file. Why do they constantly change the files??
But the other issue I'm having is, I can no longer sync my iPhone 11 running iOS 15.2.1. Whenever I attempt to sync, the iPhone connects and backs up, but halts the syncing process at that point and does not sync Photos or Music. I have since updated my two Mac Airs to Big Sur, and can access my photos on them once again, but they too will not sync with my phone. I suspect there is a problem with the Big Sur photos file now that it is changed. Anybody else had this problem?
iMac 27″, macOS 11.6