Comment by duggan
I had a similar set of tapes, and ended up collecting a chain of connectors – firewire cable, firewire to thunderbolt2 adapter, thunderbolt2 to usb-c.
Instead of cobbling together an impressive array of tools though, I just got a trial of Final Cut Pro and pulled out everything with that. You can get what I think is a three month trial? Anyway, it was plenty for this one time effort of digitizing old Hi8 tapes.
I think I did end up using Handbrake to take the raws down to a reasonable size to give to family members, but the raw footage and project files I stuck on a couple of 1TB Sandisk drives to keep in physically separate backup locations.
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.