Skills. If you want to play the piano well, you need them. Kinda doesn't matter how you get there but you need to be able to move your arms / hands / fingers in such a manner as to make the kinds of music that you want to hear. Things like scales are not particular to any specific genre of music but knowing them and being able to play them well may be helpful in your being able to play whatever it is you want to play. Knowing a little something about chord structures may also be helpful. Knowing a little something about how fingering works might be helpful. Knowing something about timing and rhythm will be helpful.
Classical is one way to develop some of those skills. But there are other methods and other teachers. Suzuki is one that comes to mind which puts an emphasis on ear training, which is a good thing. Being able to actually read music off of a page is a good thing, too, they're not exclusive.
It may be that finding a piano teacher that understands that you have no interest in classical music might be helpful as well as they may be able to direct you into paths where you'll learn the skills, just not have to be bothered with classical music. There are some out there that teach over a multitude of styles.
Something I do find interesting is an interview of Oscar Peterson talking about his early days at the piano. He had a classical piano teacher that made him play a lot of classical music that he had no intention of playing publicly. It allowed him to develop skills that transferred very well to his style of jazz. Stuff like the big left handed chords of Liszt or the right handed runs of Chopin, skills he used for his own purposes, not to copy Liszt or Chopin.
If you expect to play, you have to play something. Classical, pop, jazz, it really doesn't matter what genre, but you have to challenge your abilities and develop skills.