Spotify
Simplicity
User can change gender through simple form.
User can change first name through form.
Public identity and privacy
Users may change their display name, but public user id is immutable.
Spotify allows changing name and gender with a simple form.
However, username can't change. This username is public, because it appears in the URL on profile sharing.
It seems that this problem does not exist for new accounts, because usernames are random letters and digits, but this is still a problem for old accounts.
It is possible to obtain by contacting support that they migrate playlists and other data to a new account. However, according to support, listen history is lost, with all playlists autogenerated by Spotify. But some users report not having this problem, so if you have met the same situation recently, please report us!
Last update on June 19, 2020