We are not expecting large QCs showing up out of nowhere, breaking sec256k1 keys in few seconds.
That's not a reasonable expectation, when you consider the range of adversaries
Hashed public keys are safe in such a transient phase and what I absolutely don't understand is why we should include a proposal about public keys being exposed for an eternity waiting for their turn to be destroyed by any innovation or technology that shows up?
That depends massively on how long this transient phase lasts.
The safest thing to do is as suggested in the stackexchange article: soft fork to prevent ECDSA transfers, but invoke zero knowledge proofs of BIP32 seeds to indirectly spend them to QC resistant keys.
maybe if you find this so compelling, you could start working on the zero-knowledge proofs to spend ECDSA outputs to QC resistant keys? Like, today for instance? (you'll be busy a while hopefully
) Won't your super coin (or is it a Bitcoin fork, I forget) need it, or will you stick with hashed public keys? We don't want to hold you back, off you go...