I'd also argue he almost certainly saved a huge number of lives with Silk Road: the ability to view eBay style feedback and chemical test results makes buying illegal drugs far safer than buying them on the street. On Silk Road people could buy from a reputable seller with a long history of providing unadulterated products, and could view testimonials from other buyers who had sent the products for chemical analysis.
DPR is according to his defenders a symptom of an overly active justice system prosecuting crimes that shouldn't be prosecuted. Though I'm not sure I personally agree with that.
OJ was just a crook.
Most people seem to think Ulbricht was guilty, and deserved to be found guilty and go to prison, but that the full sentence didn't fit the crime.