If a writer needs to advertise it’s a sex scene in order to be a “sex scene”, then I’d think something is lacking in the writing. Now, in certain contexts, a “fuck me” or “bang me” might be indicative of a character’s personality, or maybe there’s a scenario the two (or more) are roleplaying. (Though, I suppose you could have it be solo, somebody watching a B/C grade porn film.)
Now, in the sex scenes I write, if there’s profanity, something’s going seriously wrong for the characters, or a copper’s busting them.