Mac OS Finder iPhone wifi sync gets stuck. Need to force shut down Mac then restart to fix.

This was reported in 2021 by Chris, with no satisfactory resolution. It has happened to me on and off ever since wifi sync was removed from iTunes and put into Finder.

1. Plug in iPhone to recharge )same thing happens with two phones).
2. iPhone wants pin to trust the computer for a back up, sometimes after up to 20 second delay. If the code is not put in, sometimes it still shows on the phone control centre as backing up, and on Finder as backing up.
3. The supposed backup does not stop, even after a few days, and even when the phone is removed from wifi.
4. A new backup or sync on the phone does not work.
5. Ejecting the phone from Finder does not work because it is supposedly syncing.
6. Shutting the phone down and restarting usually does not work, but sometimes does.
7. Mac from Apple menu shut down is blocked because an iOS device is supposedly syncing.
8. The only solution so far is to force shut down the Mac with the power button, and restart. The supposed sync disappears on restart.
9. Mac and phones are using the latest OS updates. iPhone 12, Mac mini M2 2023 (but this used to happen on 2016 iMac as well).