IIRC HTTP3/QUIC mandates TLS[1][2] so it itself still relies on TLS. It seems like it's set on TLS 1.3 as a baseline and I would hope the negotiation of the protocol is future compatible but I will admit I haven't fully read the RFCs.

[1] https://datatracker.ietf.org/doc/html/rfc9000#section-1 [2] https://datatracker.ietf.org/doc/html/rfc9001