If ASIC cryptocurrency miners could find collisions for an entire key in a reasonable lifetime, cryptocurrencies based on scrypt would be literally worthless. B

If ASIC cryptocurrency miners could find collisions for an entire key in a reasonable lifetime, cryptocurrencies based on scrypt would be literally worthless. But, they can't. They can find partial collisions. ASICs for SHA256 don't break SHA256, and ASICs for scrypt don't break scrypt.