Reason: “Paswordless” login with getting a confirmation mail each time I want to login kis much more cumbersome. (i.e. bad usability)
(Also it is not as secure, but that may not be top priority here.)
If you don’t understand it, note that I do – as anyone obviously should – use a password manager and thus clicking on a link in a mail is totally awkward to just login.
I’ve explained that whole topic already here: https://discourse.mozilla.org/t/allow-usual-mail-password-login/18192