My favorite is all these letter-soup Firewire-to-USB convertors which are just glue and random wires inside and are either completely inert or disastrously damaging to your peripherals:
https://www.amazon.com/s?k=firewire+to+usb+adapter
It's fascinating to me that every letter-soup brand is competing on a product that is literally fraud.
I literally got a Firewire to USB converter yesterday to try and pull video off a DV Camcorder. A video capture card in the same price range had worked great for letting me stream VHS tapes through OBS Studio.
There are various YouTube videos showing a daisy chain of Thunderbolt 3 to Thunderbolt 1/2 adapters connected to various Firewire cables and adapters. I was hoping to avoid all of that but the camera doesn't show at all. Fortunately, nothing seems damaged on either side.
I've only got 6 tapes so I'm sending them off to a service and sending the adapter back to Amazon.
It’s not even possible to convert between USB and FireWire without active electronics, as the signals are not compatible in the slightest.