Honestly, I think it's just easier and better to create thinly-veiled expies of real people.
I mean, an awful lot of Fantasy is just alternate takes on Lord of the Rings or Conan the Barbarian, but if I saw two stories on this site,
one called "Conan the Fuck Man" (Fan Fiction) and one called "Legend of Corgann the Conqueror" (Fantasy), I would absolutely
choose to read the second one over the first one.
Similarly, If I saw "Taylor Swift gets Banged by Big Cocks" and "The Fallen Pop Star (Starring Hayley Fast)", I'd sooner choose the
less obviously real one. I'm often in the mood for some dark, non-con stuff, but if it's specifically about a real person I get leery.
Like, if it's a fake person, I can easily project any resentment or frustration or Women Problems onto her, but Taylor Swift or Kim K
have never done anything to me, so I'd just feel weird...
A story about a hot weather lady getting fucked with sounds like a good idea, but if I then found out she's the real-ass weatherwoman
for a local Delaware TV station that the writer just has a weird boner for, I'd be pretty turned off.
Plus, if you keep it vague, other readers can project their own favourite celebrity's appearance onto the character and not be confined
to just one character.