There is not risk at all, even if people try to brute-force all the PK with Quantum Computers they will not a success because the number of private keys is really big even for Quantum Computers. But if they can vuln sha256 there is always the option to fork the core and implement a better sha solution like sha512.

It is fun to see how people are worried about quantum computing and bitcoin. If that technology really can damage bitcoin, the crypto coin is the smallest thing to worry about in that moment, because it would mean all the military systems even the nuclear plants' systems will be in danger too.