PowerSDR KE9NS v2.8

I understand the adapter dance - going from FireWire 400 to FireWire 800 to ThunderBolt 2 to Thunderbolt 3. But once there, can I plug that Thunderbolt 3 connection into a regular USB-C port? I believe USB-C is faster than FireWire 400 so transfer speed shouldn't be an issue.

I thought the cables for USB-C and offical ThunderBolt (with the lightening icon) were compatible and it was just that USB-C would not be as fast.

There is so much cost (the adapters) in moving to a smaller/faster/Win 11 PC, I'd like to avoid the cost of needing that newer/better/faster box to also support ThunderBolt if the USB-C will do?

Another concern is I see the miniPC's that say they have ThunderBolt but I only see a USB-C connection - no lightening icon. Maybe the lightening icon is just an Apple thing?

I have an old Intel box running Win 7 and a firewire card. But it's not going to run forever (neither am I). It will already cost over $100 just for that adapter chain. I could save about $200 on the MiniPC if that last ThunderBolt 2 to ThunderBolt 3 adapter could work with the USB-C port.

As far as I am aware, nobody has created a USB3 to FireWire adapter. I do know they have a USB2 to FireWire device, but its only good for transferring photos across FireWire (DV) Sony cameras.
Even though Apple created a Thunderbolt to FireWire adapter, they dont make it anymore, so you would need to find a used or NOS unit.
But USB-C is only Thunderbolt if you see the thunderbolt logo next to it.
So the only current production would be a PCIe or mini-PCIe FireWire card (and use a M.2 adapter if needed)

Apple is definitely the biggest supporter of Thunderbolt (just like they were with FireWire back in the day)

Darrin