I'm currently building a framework agnostic Authentication module for PHP/Composer, that has 2FA baked in. I want to give everyone who's building web apps in PHP no excuse for not having it. It's painful, but worth it IMO.
And I thought that dropbox had already lost their reputation with pretty much everyone around since those massive security flaws exposed a while back. Silly me.
If the service you're using doesn't support it, ask them to implement it. If enough people did it..