Earlier quoted context omitted.
You could make the case I've just been indoctrinated in this stuff (genuine believer) but I take that to be a profoundly progressive verse given the context Paul is writing. Notice the symmetry.
I do notice the symmetry. It is saying that each of them can use the others body as they like, without regard for the other. But that's fine, because they can do it right back. A progressive system is not built off "I'll do what I want to you but I also will let you do it back". That conveniently ignores that there is still an entirely non-consenting party in this. Your body belongs to you. Your partners body belongs…
It's ok to set aside misgivings about the whole thing and how the world has corrupted it all and just explore the possibility of depth and beauty and love. You don't have to chose the worst interpretation of things, even if others have.