My point is that QC tech is currently publicly available. I would anticipate it will continue being publicly available, probably a few generations behind the 'state of the art' technology.
It is. I just don't see the point if they aren't sufficient for doing anything as much as attacking Bitcoin, nor would I think that anyone in the public would be able to have access to such technology at least until the point when the relevant cryptographic algorithms are phased out.
I have made similar arguments in the past, and I stand behind those arguments. I don't think this means QC can be ignored though. Once the West and the Communists in the East (most likely the US and Chinese respectively) have QC tech, knows the other side knows they have QC tech, and knows that the other side knows they have QC tech, the incentive to keep the technology under wraps goes away.
If QC technology is used to crack bitcoin private keys, it will probably be too late to move away from EDSCA and confidence in bitcoin security will be lost/damaged. Using QC technology to crack bitcoin private keys will also cause a lot of damage throughout the bitcoin economy, and it has the potential to cause a lot of businesses to go out of business.
The threats of quantum computers are very real. That does not discount the fact that the incentives to attack Bitcoin pales in comparison to the other things that you can do with QC. You're assuming that we won't be able to at least adopt another QC resistant standards before it becomes a threat. Long before Bitcoin becomes a target, I would assume that we would've adopted another QC resistant algorithm. QC technologies seems to have an incremental improvement over the years and I don't think that a 2000qubit QC machine would be discovered overnight. As a state, I would think that they are more interested in collecting encrypted information rather than cracking a few Bitcoin keys, and I think the estimates for a ~1500qubit machine puts it at one PK per hour. I'm not exactly sure of the running costs of a quantum computer but I would probably think that it's not worth their time at an early stage where you would probably need a very precisely controlled conditions to keep it stable.
Yes, Bitcoin will definitely be affected by QC but the fact that it *probably* cannot be mass produced in the first place will bring about some doubts if people would want to start cracking the keys if they (the states) could stand to gain much more by starting to decrypt previously intercepted internet traffic. Anyhow, I would regard all of the discussions as speculations. If quantum computers gets cheap enough and collecting money is their main goal, then attacking a currency like Bitcoin could make some sense though the effects will be limited.