There’s a lot wrong with what you said.
PQC is a new set of standards (FIPS 203, 204, and 205) describing digital signature schemes and key encapsulation methods that are resistant to a quantum computer’s computational advantage. These methods involve public key cryptography and are asymmetric.
AES-256 is a symmetric encryption method and PQC has nothing to do with it.
The article in question mentions one of the key risks of not introducing quantum-resistant methods: harvesting the encrypted data and waiting for a future date to decrypt it. This is a real risk, and breakthroughs in this field are difficult to predict. Considering the fact that NIST’s guidance applies to most of the federal government, it is prudent for their strictest forms of security standards to provide a high level of assurance against state-level threat actors.