@jaddy
No, we don't plan to add more support for OAuth2 until providers stop the practice of requiring client registration: https://support.delta.chat/t/outlook-no-longer-accepts-classic-authentication-methods-to-sync/3281/2

We supported OAuth2 for Gmail in the past. First they required us to justify the need to get full IMAP access and then they updated the requirements and revoked our client ID: https://github.com/deltachat/deltachat-android/issues/3233

Not going to repeat this mistake again.