yes of course that would be a fairly simple way to solve... I'm just curious that I've not heard about any blockchains doing so, especially with all of the Quantum hype... cryptos love to ride hype trains...
As you said it yourself, it's still very much just hype. We are miles away from any practical solution that will put the current algorithms in danger.
But seriously, it would make more sense to implement quantum resistant cryptography before a quantum computer is created than after.
The implementations of quantum computers that we can see today are extremely delicate. They can barely function in perfect laboratory conditions. I think there is no need to rush ahead and deal with hypothetical problems that may never turn out to be actual problems.