I'm not sure what asymmetric encryption has to do with this.

There are already protocols that are widely used in ham radio that support encryption. For example, DMR supports encryption (because DMR can also operate in commercial bands, under different laws), it's just not used for ham radio and I've never seen a ham turn it on. Wifi supports encryption, and ham radio operators using it in ham radio bands (with more power) actually turn encryption on but document the PSK publicly (in an attempt to keep the non hams out, but make the encryption more an encoding that anyone could decode).

In my experience, ham radio operators generally roughly follow the rules.