you say this like it's a bad thing. Haven't you noticed that most of the people on Survivor los a lot of fat but maintain their muscle. Haven't you ever wondered why. Doesn't it make you question what you know about nutrition.
from a evolutionary standpoint your wrong. will the body maintain baseline muscle mass-yes. the diffference with bodybuilders are they have hypertrophied muscle which takes many extra calories to maintain, which from this standpoint is a negative. the body will go back to homeostasis if you let it. in starvation conditions excess muscle mass is an extreme negative, less calories equals less muscle. why would the body hold onto extra muscle which is energy suicide?
it wouldn"t the guys on survivor maintained baseline muscle, no one is saying you cant maintain a level of muscle(your body needs it) you just wont maintain any appreciable size hence adonis, and they way you look. both small with little muscle.