There is no question in my mind about this, in fact.
Yes, there were problems with retired players complaining about Upshaw's union not being sensitive enough to their needs. And yes, Upshaw was often antagonistic with the NFL powers that be.
But in the end, he did more to benefit players of all eras than most union leaders can ever hope. He inherited a union that was nearly broke and was essentially dysfunctional in 1983, and he turned it into one of the most powerful unions in any industry.
Here's my take on Upshaw in today's Newsday.