I don't know if this applies to your situation, but I migrated from my old Mac Pro to my present iMac using a Thunderbolt to Firewire adapter For some reason, I couldn't get ethernet to work (and the same happened a few years ago when I tried it with a friend's computers).
MacBook Pro - M2, Ventura 13.6 Safari Tech Prev 17.0 Safari 16.6 Firefox 116.0.2 iPhone 7 Version 15.8