WD WP Pro and Macbook Air M1

I had the very same issue as you using original Apple adapter USB-A to USB-C.
Luckily I had USB-C/HDMI adapter, also Apple Original (USB-C Digital AV Multiport Adapter) and then I realized it only works with this adapter.
Tested on all USB-C ports using the USB-C/HDMI adapter and it works fine.

My conclusion: Original Apple USB-A to USB-C does not support this type of connection.
(Please correct me if I’m mistaken)

Hello guys, so I can‘t say if it has something to do with the different brands of the adapter, but what I can 100% say is that:

Try to connect the drive to your M1 and turn it on, than turn if off again and redo this process until the light of the HD is not blinking anymore, which means it is in the mounting state! … so maybe this workaround is working with any kind of adapter!!

greets from Germany.
Matthias