"While low-paying firms squeeze every penny from pay, high-paying firms bid for talent as if they’re at Christies."

By "talent", you mean those workers who are measurably superior in their field to all of the others. Look at professional sports. Most minor league players don't even make enough to live on, and college players aren't paid at all, but when they hit the big leagues they make millions. Obviously they are worth that much more than run of the mill players.

The overall inequality is to a great degree measured by the fact that some people are far better than others in doing certain things that have value. The only way to keep them from rising above the others is to hold them back somehow, and that is a horrible idea since the innovation you speak of is still probably going to come from them.