No, v3 isn't TLS either. TLS is only used as a connector between hops (so the client connect to a node using TLS, and the nodes connect to each other using TLS), but that is it. (I think, if I'm wrong do tell me. I didn't go check the spec)
https://gitlab.torproject.org/tpo/core/torspec/-/blob/main/r...
I think the main question would be: are there cryptographic attacks that a rendezvous server could do that wouldn't work against TLS?