My TB3 mesh network shows interfaces as thunderbolt0 etc. this is on Linux using thunderbolt _net from the kernel. Latency is worse than regular twisted pair Ethernet.
I was seeing 1-1.5ms latency using linux bridges for the mesh. Not a huge issue for ceph replication but significantly more than switched lan. It may be possible to get it lower with routed instead of bridged but my understanding is thunderbolt_net on Linux is not perfect in that regard.