MFA is not a magic solution to all problems either. You can't expect me to give my phone number or real email address to every random site I login into.
This is why I'm a big fan of the U2F standard, which allows a device (generally a small USB/NFC device) to generate shared secrets for arbitrary services without exposing any personal information.
Think about this problem in context with the NIST trust level framework.
Nobody gives a shit about low trust environments... go ahead and crack my slashdot account, but higher trust stuff like mail, money, network access etc absolutely need MFA.
That's my point. MFA itself is certainly a very useful security solution (for example, I wouldn't trust a bank that doesn't use it), but "MFA everywhere" is not a way to go, because I value my privacy more than some useless Internet account.