Sonically similar radios

QQ- Are sonically similar based radios, track and album, affected by degrees of separation in the same way that artist radios are?

Sonic similarity is a sliding scale, there are no degrees per se.

Does that mean that artist radios are now based on the “Sonically Similar Artists” and not the “Similar Artists” and so the degrees of separation setting applies accordingly to the former?

They’re based on both, generally.