I don't think 2FA should be mandatory. Leave that decision to me, the user.
For some kind of admin account with privileged access to other users' data, then it definitely affects others.
One might expect increasing mandatory security measures correlating with increased potential damage of a breach. Similar to safety measures on mass transit vs. personal vehicles.
I’m sure most people on HN have great passwords stored in password managers, but 99.9% of users are not like that, so mandatory 2FA does not only make sense, it’s the only reasonable choice for sensitive information.