This might be answered in a more timely fashion at the Apple forums here. This is a Dell PC forum.
I've just bought this adapter to connect a Thunderbolt 1 RAID to an M1 Mac Mini. Plugged it into the Thunderbolt 3 host port on the Mini and it simply isn't recognized at all in the system report - no device showing on the bus. Same on an Intel MacBook Pro. But if I plug it into a USB-C port (not Thunderbolt) it is recognized as a USB device. What exactly is happening here? Both machines on MacOS 12.0.1
Thunderbolt 3 adapter not working M1 Mac Mini