Comment by Clamchop
No need for FCP, as iMovie can still capture DV streams from Firewire. I'd expect they both use the same implementation.
However, Apple has removed Firewire support entirely from macOS Tahoe so none of these solutions will work on Mac going forward.
I think it was needed for retaining the original aspect ratio, and capturing in ProRes, but maybe there's a workaround there that I didn't find.