[peblos]

“For example, I’ve been using a password manager for the last two years, and now all my passwords have been generated automatically. This means that if you steal my password you’ll only have access to one of my accounts.”

At risk of stating the obvious, this misses the point of MFA.

Password managers are not an alternative to MFA. Also, how do you enforce the usage of a password manager such that you can confidently remove the requirement for MFA?

The whole idea is to protect the one account. If you “only” lose one account that’s still a bad day. Service1 has no ability to protect Service2, so protecting all of your accounts is not something MFA tries to solve