Glenn Gould’s interpretation of Bach is so definitively his own. One of the things I love so much about Bach is the distinct absence of phrase-markings, dynamics, and tempos. It fits in with the idea of Bach The Improvisor.
Bach gives us the important information (what notes to play, and for how long to play them) and the rest is up to the performer. Each time you play, it is an act of improvisation.
The line between “classical” and “jazz” is only there because there are those who would profit from their segregation.