The idea that quantum computers will destroy Bitcoin has been trending online again recently, but haven’t you ever wondered whether the actual risk might not be that significant?

I noticed while reading a report that CoinShares put out the other day, and realized that the commonly said claim that “20% to 50% of all Bitcoin” are vulnerable to quantum attacks is mixing up theoretical risk and actual risk. It seems that the possibility of being stolen at a level that can truly affect the market is limited to only a very small portion.

Specifically, it’s said that around 1.6 million BTC stored in old P2PK addresses—about 8% of the total supply—is vulnerable to quantum attacks, but of that, the scale that could actually cause “notable market disruption” is only about 10,200 BTC. The rest is spread across more than 32,000 UTXOs, averaging about 50 BTC each. With such fragmentation, it would take an enormous amount of time for an attacker to decode them one by one, and there’s a high chance they’d be detected in the process.

To begin with, breaking Bitcoin’s cryptography seems to require a fault-tolerant quantum system with performance 100,000 times greater than the most advanced quantum computers currently available. Google’s Willow is a 105-qubit machine, but the story is that key-breaking would require several million qubits. In other words, this threat is at least 10 years away—not an emergency, but a technological challenge that needs to be addressed over the long term.

With recent market instability, investors are in the situation of looking for “any structural risks,” so that’s probably why the talk about quantum threats is coming back up again. But most developers view this as a problem for the distant future. Critics point out that “it’s a lack of preparedness, not the timeline,” but I think it can be handled sufficiently by proposals like BIP-360, which would move gradually to post-quantum signatures.

My personal view is that, even for these kinds of technical challenges, Bitcoin has the ability to absorb them over time. Maybe it’s more important to take a long-term perspective.