Oshiete. my teacher!
I think people have done that several times this saga, each time something glows in a preview I seem to see posts getting excited about it.
But yeah, Mallow's goal sucks. Why couldn't it be anything Pokemon related?!
This show has established dozens--no, hundreds of times that "being a whatever Master" isn't the end-all-be-all way of life.
There's more to this world than battling and Contests and whatnot.
Hell, the Eevee sidequest in the Sun and Moon games outright destroy that idea.