In general, tunneling through HTTP2 turns out to be a great choice. There is an RPC protocol built on top of HTTP2: gRPC[1].

This is because HTTP2 is great at exploiting a TCP connection to transmit and receive multiple data structures concurrently - multiplexing.

There may not be a reason to use HTTP3 however, as QUIC already provides multiplexing.

I expect that in the future most communications will be over encrypted HTTP2 and QUIC simply because middlebox creators can not resist to discriminate. It may even be necessary to serve some random (perhaps AI generated) HTTP2/HTTP3 content to mitigate active probing[2].

[1] <https://grpc.io>

[2] <https://blog.torproject.org/learning-more-about-gfws-active-...>