Should a famous singer contribute to the film's soundtrack?

I've noticed with a lot of films that have a prominent woman based fanbase tend to have a pop star contribute to the soundtrack such as ellie Goulding with 50 shades of grey or Lorde with the hunger games.



Wouldn't it be fun to see someone like taylor swift have a music involvement in the movie? I wasn't a fan of hers til her latest album but a song like blank space for carol would be amazing.



What do you think? Haterz to the left