Bluetooth between iPhone 13/iPad Pro (running 15.1) and Macs running Monterey (12.0.1)

We've been able to verify that every Mac upgraded to Monterey 12.0.1 no longer allows iPhones or iPads running IOS or iPadOS 15.1 to connect via Bluetooth (iMac Pro, Mac Pro7,1, iMac). The phone reports the Mac as incompatible and forces a "forget". The Mac seems to connect for a few seconds then loses the connection. Resetting the module (safe boot, remove plist) has no effect, rebooting/resetting the iPhone has no effect. None of the standard Bluetooth troubleshooting steps has any effect at all. The two systems seem incompatible at this point. All out other peripherals seem to work so far -- even on both the Mac and iPhone.

This is VERY consistent across dozens of systems and phones. Is anyone else seeing this or is it something in our environment?