I was talking about this last week when the news about Google's quantum computer was making the rounds. Research physicists who study the progress of quantum computers are now warning that we are 5-10 years away from commercial quantum computers that can break the encryption holding the blockchain together.
"We are about five years away from commercial quantum computers being able to break the elliptic curve keys that secure #Bitcoin wallets,” said Pierre-Luc Dallaire-Demers, a scientist-in-residence at the University of Calgary
This is real issue that we need to start addressing now. Because if the blockchain's encryption is no longer secure, the entire Bitcoin ecosystem is going to fail. Quantum resistance needs to be planned, and applied to the blockchain through a comprehensive update strategy. Such a strategy may hurt temporarily, but the alternative is to kiss Bitcoin goodbye.