If will agree in this point, then this activity can be enough to punish Ulbricht lifetime in prison for the amount of the bad make with him's help. Which was not a lateral but basic help. Without this help anything would be possible. He offer basic help in (repeat) the disease and distress of thousand and thousand people and for more, even earn money doing this bad. Have nothing to do here the spread of legalization of the drugs (even if it will be so). We are speaking about a fact. Repeat: He offer basic help in the disease and distress of thousand and thousand people and for more, even earn money doing this bad.
What Ulbricht provide is a market for trading so called illegal drugs and other goods. If those goods are traded in a face to fact manner, then there will be more gun battle between drug traders and will waste a lot of police time.