@aral I talked about this issue in a post for Purism recently. As you allude, the prime motivator for this move to the passwordless future is to anchor trust in these vendors so people are dependent on them for security. Passwords are one of the last areas where a person has some level of control over their own security in these ecosystems.
https://puri.sm/posts/microsoft-ruined-passwords-now-aims-for-a-passwordless-future/