Having worked in this industry myself, is it definitely a talent to have good stage presence, good presence in front of a videocamera, photogenic and modeling skills. Not to mention charisma when dealing with radio and TV interviews, fanbase, etc.
It's also a talent to sing well, to sing consistently, to be able to channel inflection and emotion on command in a studio or on a stage.
There is more to being a pop star than the songwriting.
(Note I'm saying all this while still holding huge respect and value for the songwriters and producers themselves. I'm a total music fan.)
You could be VERY plain looking, and unable to dance at all, and chart in in 1965.
Disclaimer: I have perfect pitch since I was a kid, can hold a note when singing, made a lot of music as a kid (guitar and electronic), had some singing lessons and yet I'm at best a fun karaoke singer to listen to when you're drunk.
Without comment on the state of pop music, you don't actually mean to suggest that performance isn't a talent of it's own? How are you going to and sell that idea to Yo-Yo Ma?