I personally don't bother too much just because if someone Google, 3 letter agency or even aliens will come up with a quantum computer satoshi's funds will be the last thing that we'll need to worry about.
Just think about all the "password protected" (encrypted) things that are out there, like: financial system servers , electricity servers, medical care servers, airplanes servers, nuclear missile codes. These are things much more valuable and important than 1M bitcoins.
How about in a decade or two, when Bitcoin's market capitalization might be in the trillions, or tens of trillions? Valuable enough?
We're also talking about much more than 1 million bitcoins. It's 5 million+ that have exposed public keys and theoretically
the entire supply if QC is capable of breaking transactions in flight.
Centralized infrastructure also requires far less coordination to secure. In a zero-day situation, governments and banks could react far more effectively than the decentralized Bitcoin network ever could. If QC broke ECDSA in the wild today, I don't think Bitcoin would ever recover.