Clickbait

ALL transactions that use P2PKH are quantum secure without a hardfork. There are no known quantum algorithms against hashfunctions beyond grover

Since this puzzle depends only on the pre-image resistance of RIPEMD-160 (not on any elliptic curve assumption)

ECDSA also do not rely on an "elliptic curve assumption". They rely on the the Diffie–Hellman assumption. The elliptic curve is only the group on which it is calculated.