The difference between McDonalds and sex work is that the employee isnt giving up their dignity and their body autonomy for someone else’s use

They get treated like shit by their boss and society, and told what to do with their body and when. They absolutely are giving up their dignity and bodily autonomy.

Pretty sure a few thousands generations of people figured out how to have sex and enjoy it before porn came along

(This is of course ignoring your implication that people who watch porn cannot have and enjoy sex as well.)