Aside from what @tromp said, IIRC QC allows faster QC brute-force collision attack on SHA-256 which reduce 2^256 range into 2^128 due to something called Grover style speedup.


By default, i would treat it as "snake oil". There are other real and more reliable ways to guess BIP39 seed phrase, such as finding out weak RNG used by one of Bitcoin wallets.

Aside from what @tromp said, IIRC allows faster QC brute-force collision attack on SHA-256 which reduce 2^256 range into 2^128 due to something called Grover style speedup.


By default, i would treat it as "snake oil". There are other real and more reliable ways to guess BIP39 seed phrase, such as finding out weak RNG used by one of Bitcoin wallets.