However, if you are the first one and nobody is able to do this then this is the right thing to do. The first few addresses that are compromised this way will send a panic wave and stir up stuff to the point of attack discovery. Since a quantum computer can only attack addresses which are reused, a pattern will emerge quickly.
Of course the question is "how do you know you're the first/only attacker"? Cracking the first key would probably take months or years of effort (if someone tries with a QC of some dozens of thousands of qubits and barely the ~2500 logical qubits necessary to crack Bitcoin keys), and thus I think this would be a risky stealing strategy. But I don't want to argue further here, it's of course still possible that the attacker tries it this way, e.g. if a very rich entity is directing a lot of effort into developing such a QC in secret.
This would help. Without intending to, some wallets that are limited in user features actually end up doing this. In some of them you can only generate the next unused BTC address and it is very difficult or even impossible to see previous addresses.
I've started a
thread here about that topic, and may file a feature request for Electrum at least.
Only sending or receiving coins to newly generated (change) addresses has the problem that if you already got at least 2 transactions to a single address (and thus several utxos are associated to the same address), and then transfer funds from that address, you would not automatically move all coins to a safe change address if one of the utxos is not needed. Thus I think what current wallets provide is not enough to really help reducing the number of vulnerable coins.