and/or detect that the user was an IdP managed user?
In the reconcile lambda from the IdP (here's the docs for the OIDC lambda), you can set whatever data you want on the user.data field, so you could set user.data.idpUser = true. Then you can access that value from the self edit page freemarker template and decide to show or hide the password field.
I get that this isn't as straightforward as it would be if the original feature request was implemented 🙂 . But I think there's a path forward here that doesn't wait on that.