Cannot Use Thunderbolt Accessory - when plugging in to USBC port

I have an OCW thunderbolt drive that I have been able to use as both thunderbolt and usb-c drive on my older 2020 iMac. I just upgraded to the M4 Mac mini with Studio Display, but the drive will ONLY work on the rear thunderbolt ports on the back of the Mac mini. Will not work on the front ports, or on the ports on the back of the studio display.

What's the reason for this difference?