Ugh that quote is so cringe-inducing
Like Alex says, Jarrett is notorious for being an unpleasant, egotistical douchebag in general but that's pretty bad, even for him. And there's not a grain of truth in it- he's not even close to being one of the most influential pianists in jazz and he himself owes quite a bit to Bill Evans, who preceded him by a decade and is a far more accomplished soloist and composer. But hey, when the cornerstone of your career is a live album consisting of you doing some very safe and unimaginative picking around on a noticeably out of tune piano, it makes sense that you'd maybe wanna do some myth-building.
Sorry he's sick but yeah he's a dick.