Bitcoin won't survive if a successful Shor's attack happens before Bitcoin's quantum immune system has developed to a specific degree. Right now nobody can say whether the virus will hit before or after the immune system is at that point (if the virus will hit at all).
But one can make a very strong argument that it hitting before is within the realm of possibility, and that as a result that would mean the end of Bitcoin.
True, but the solutions are already on the table. Bitcoin could adapt in a matter of days if something happened.
Wouldn't help.
If a well-prepared team (say in Asia) had a quantum machine capable of running Shor's to break sigs they could potentially take 30% or more of total Bitcoin supply within the first day. That would be a knockout effectively. They would have pre-cracked the private keys of tens of thousands of the richest vulnerable addresses, and likely a lot of the smaller ones, down to a pretty low bar. And any attempt to move bitcoin to a wallet without an exposed key while this mayhem is going on is open to active interception. Basically 30% is guaranteed, 50% is on the cards, and it would be over before it began, assuming the goal is to end Bitcoin and cause chaos (potential military goal), and not to slowly and quietly get rich.
That again assumes it happens before Bitcoin has any real immune system in place. Which hopefully isn't the case going into to 2030.
