Describe the solution you'd like
With the ability to sign up/in now with OAuth2, the option to only allow OAuth2 and remove the default email and password fields would be a great feature. This could be accomplished by adding a new optional environment variable to "hide" or remove the default email and password fields. The optional environment variable would have a default value of false (not hidden) and only used when ENABLE_OAUTH_SIGNUP=true.

Describe alternatives you've considered
Able to disable signups with environment variables but this does not remove the username and password fields resulting in a undesired cluttering when only wanting to use OAuth for logins.