I had heard that Big Sur stopped supporting Firewire. I have a MacBook Pro running Mac OS Catalina and Capture One Pro 20 that tethers to a P25. After the upgrade to Big Sur, connecting the digital back causes the computer to kernel panic.
I do have another Mac that still tethers fortunately. But I can say through personal experience on equipment that used to tether via Firewire that Big Sur no longer supports Firewire (even through Thunderbolt).
I do have another Mac that still tethers fortunately. But I can say through personal experience on equipment that used to tether via Firewire that Big Sur no longer supports Firewire (even through Thunderbolt).