Not really. HTTP3 has little benefit (if any) when talking to a backend server, plus browsers only support QUIC with TLS and you probably don't want to waste CP

Not really. HTTP3 has little benefit (if any) when talking to a backend server, plus browsers only support QUIC with TLS and you probably don't want to waste CPU cycles terminating TLS on an application server and leave it load balancer (that isn't written in nodejs and supports HTTP3)