Isn't there still need for non- or post- FIPS-140 -like cipher restrictions in non FIPS-140 environments?

How much code is needed to implement Classical+PQ (Hybrid PQ) or PQ-only (Only PQ) cipher selection restrictions just?

FWIU, with golang:

  # This allows X25519MLKEM768 (Hybrid PQ)
  GODEBUG=fips140=on

  # This prevents any PQ ciphers from being used:
  GODEBUG=fips140=only