Why?

Yes, we are all human and we all have challenges in life, challenges that allows students to relate to their teachers.  Beyond that, we are not equal, not in our talent set, not in our approach to problem solving, or even in our attitudes about how to adapt to challenges.  If we were actually equal, no student would need a teacher. 

They come to us because they want to be equal, or better. And we should want them to be, superior to us even.  That is why we teach.  

So, my 'why? is not whether to treat someone with respect and dignity, but whether to pretend that they don't need us.  And this is not a criticism of the statement 'talk to the student as an equal' as much as a need to clarify and hone what that means, because without that clarity, it may have negative implications on classroom management, student engagement, and student success.