Stallman made a huge mistake: he forgot that he too is biased. Just like Lessig's defense of Ito damaged Ito and Lessig more than if Lessig had just STFU Stallman did the same for Minsky.
And Stallman being his usual amicable self he managed to do so in a way that a reaction was inevitable. If he wanted to do right by his friend he should have pointed out the flaws in the accusation, not to try to find some contorted way to argue that assuming it was true his friend should have walked without consequences.
Lessig falls into exactly the same trap, the fact that it is your friend who does something stupid or despicable does not make it any less so and in cases like that your friends would be better friends if they pointed this out to you. Preferably at a time that it would still make a difference.
Minsky may not be guilty of anything, and Stallman has shifted the debate over whether what he assumes Minsky has done should be legal or not (it shouldn't, let's be 100% clear on that) over whether or not it happened in the first place. And that is not helping at all.