True enough, although I also see a lot of alternative issues that arise from this model. This sounds like it requires you log into your email or your android or something. Which sounds like a lot of extra time involved.
SQRL is nearly instant and already a complete solution which accommodates for a lot of security considerations. Its basically similar to OAuth minus the third party.
I do suggest taking a glance at it I think you might be impressed with its overall design. It really eliminates a lot more than what I wrote. I was just hoping to highlight some of what really stood out to me.
I am curious what the usual cost for something like this is.