I typically turn my Spotify app on once I start playing GT Sport. I do sing along to some of the GTS tracks when I do listen to them though, especially "Je ne veux pas travallier, je ne veux pas dejeuner.." But I do not listen to any of the GTS tracks outside the game.
I do like the instrumental music in GTS though, so I will sometimes find some random instrumental playlists on Spotify or some French music playlists among others, which through those I've found some artists that I really like.
So I guess in response to the actual thread title "Has Gran Turismo affected your music taste?", then yes, indirectly.
The very first time I booted up GT$ a little over a month ago, the first song that was playing was :
"Je ne veux pas travailler..."
I was very pleasantly surprised that song would even make it as a GT track...
It really set the tone for me... And I was loving GTS within the first 3 min of experiencing it.
I already knew the song years ago and love it (being French myself), so the fact PD/Kaz included here re-enforce the fact that Kaz has very good musical taste... (For the main part, there are some doubtful instances, but I am giving him the benefit of the doubt .
My point here is that: I applaud GT/PD/Kaz for not following the typical car game music trend/feel that dictates techno electro music or Hardcore Rock are the only 2 choices (as EA has fallen flat on its face ....) ... GT dared to go where people would not go musically for this game genre, and it still works (even better), setting it apart and above others...
The fact that they allow us to run our own songs is an awesome option too... But I wish they allow us to mix between their list and ours...
For me, GT strikes as the most balanced, well rounded car game out there... Accessible but not dumb down, Visually striking and musically tasteful for the most part... IMO