You still can. The problem arises when you don't actually wanna pre-share the key, and you still want post-quantum forward secrecy. Then you need a PQ KEM lik

You still can. The problem arises when you don't actually wanna pre-share the key, and you still want post-quantum forward secrecy. Then you need a PQ KEM like McEliece or Kyber to run a PQ-secure key establishment.