Yeah this is also what I understand the threat to be.

QC can break encryption from public key to get the private key. So QC is only a threat for when you reuse an address as the public key is only exposed when you send a transaction. Though it also means the ~2 million bitcoin sitting in addresses from back in the real early days of bitcoin (when bitcoin was sent directly to public keys rather than public addresses) are just sitting around ripe for the picking for when QC gets mature enough to break the encryption. So that is the main threat, the ~2 million btc that WILL eventually get stolen by QC at some point in the future. Of course some of that btc are still controlled by people and they can move it to new addresses, but the majority of those coins are likely lost coins, and so would eventually be stolen in a QC world.

I did see recently there is some proposal about eventually essentially blacklisting those QC-susceptible addresses basically, or I think maybe the proposal was actually to have everyone move to an even newer address type and not allowing any current address types in the future, i don't remember what the exact proposal was, but that is what I proposed on here maybe a couple years ago - that unless some action is taken there will be ~2 million bitcoin that get stolen at some point in the future from QC and so at the very least that original pay to public key transactions should be blacklisted, thus preventing the threat of QC stealing those ~2 million lost bitcoin from 2009/2010 time period.

It's better to play safe than exposing yourself to threats and hoping that an imaginary fix would protect you. The quantum computing technology is advancing and I see bigger threats for reused addresses.

Do yourself a favor, don't reuse addresses and if eventually Bitcoin addresses gets quantum proof, it's a double advantage.

To give you a hint, we have a lot of threads about it,

• Quantum computing and the future of bitcoin.
• Emerging Solutions for Quantum Computing Threats
• Quantum Computers Can Not Defeat Bitcoin, not even The Bitcoin Network
• Is Willow (Google new quantum computer chip) going to kill Bitcoin?
• "Quantum computing"
• Bitcoin will be vulnerable to Quantum Computers in about 2 years

So just probably go to that thread and read everything about it. And the reason behind not using a Bitcoin addresses is that your public key will not be exposed.

Or if the threat is real then Bitcoin developers might replaced the existing SHA-256 with a more quantum resistant has function.

This is also my opinion, if quantum computers become a threat, bitcoin developers will not stand still, they will respond with a more resilient system. I hear that current quantum computers are far from breaking ECDSA or SHA-256 because of their high error rates and limited number of qubits, and moreover, they say that it will take 10-20 years to develop the quantum computers needed to break the Bitcoin network.

I'm a little bit confused on this because, my wallet generates a new bitcoin address anytime I use it. So why would it be necessary to move my coins every time I use it? Isn't that the point of the wallet generating a new address every time it is used?

Well, this topic has been here for how many years already and this is a great topic that could really affect bitcoin in the future since we're not far from having advanced technology like quantum computing. I mean we're far but as you can see in our technology development, it's quite fast and instant. Really concerning tho since it might decode the cryptographic of BTC which can be a major flaw in the future. But I'm for sure that the people behind crypto are trying to research and study more about it, ofc they won't let it happen.

It's a valid concern, but still a long way off. Bitcoin devs are aware and already exploring quantum-resistant options. Nothing to worry about right now.

In short:

1. It's not a threat yet, but might be in 10 years when they find out how to translate between languages, enabling quantum machines to read binary data and then translating it back into binary for normal computers to compile.

2. When it finally becomes a threat to bitcoin, it will also be a threat to any other secure system. How do you think bank accounts are secured? Do you think your president's email address is fine if they can crack bitcoin? What about stock exchanges, social security payments and so on?

Just how many more of these "QC threat to BTC" threads will folks create? There are literally over a dozen or more... Apparently folks are too lazy to bother checking if 'their new question' has already been discussed to death... ALL have the same answers - not an immediate problem because there are NO viable QC's yet and yes there are already solutions that exist to address it when it finally is needed.

Yes but it is still deeply in the 'make a memory cell array' (qbit) stage. We are a LONG way from making a QC that can solve even the simplest problems.