> ...and yet, somehow we managed?

People in the past put up with all kinds of struggles. They had to.

> I don't believe the argument you are making is true, but if the primary objection really is that teachers have to grade, then no, I don't have any sympathy.

I have no clue what the primary objection really is. I was responding to "I don't see why this is so hard", which just shows a lack of imagination.