For our free/individual plan we do use OAuth2 providers (currently only Google is enabled, but considering others), and can support other methods for larger teams (like oidc).

Originally the idea was to keep everything within the Obsidian UI so things like username/password didn't make sense (no password managers in Obsidian).

We initiate the OAuth2 login flow from within Obsidian. I guess we could add an extra click that takes you to our website first and then add support more auth methods from there. I don't really want it to feel like a web app though.

I'd love to hear your take. Which login method do you think is both simple and could be coherently used within Obsidian on all platforms?