In T8029#212310, @werner wrote:

My actual plan is to rework the imp[ort/export of secret keys to gpg-agent. Right now gpg-agent has knowledge of OpenPGP for import/export. This is not good and the required conversion should be moved to a helper tools for easier testing and to have this out of the gpg-agent process. For Kyber we right now don't use any conversion mut store the secret keys in gpg-agent's native format. Thus the passphrase is not necessary. We need to figure out why we have this problem here.