I first started using Spotify in 2014. I still have and edit playlists from 2014. Now, due to massive dysphoria- I will either a) have to re-do years of playlists, b) sit and deal with my dysphoria, or c) advocate for change.
I was 14 and thought I was female. Now I am 19 and male and my gender on Spotify is the same as it was when I was 14 even though that is not the case. I linked my account through Facebook. I changed my name and my gender on Facebook. Spotify recognizes the name change only when I toggle the privacy settings.
If Spotify can acknowledge a name change- then it can and should acknowledge a gender change. Spotify, I am asking you to allow your users to adjust their gender even after signing up.