You're being downvoted, but to a certain extent, I agree.
I personally find people like Richard Stallman extremist to the point of considering their positions to be cult-ish or religious. But I think people like that serve as a valuable counterbalance to the people at the other end of the spectrum who don't care about software freedom and are purely pragmatists (or who actively try to thwart FOSS).
At the very least, when bad things happen, and the people on the other side say "we never could have foreseen this", we can point to RMS and say, "yes, you could have".
Yes, but I've always disliked the idea that one extreme will balance out another. Like advocates of Fox News or CNN saying their bias is justified because is balances the bias of their counterpart on the left/right. In theory if people watched both, digested the arguments of both sides, there might be some balance. In practice, it tends to simply entrench people with confirmation bias.
I think you should consider the differences between types of extremism.
The difference between Stallman and Fox News is that Stallman's extremism is well reasoned and consistent while Fox News is only consistent in serving the interests of "the man behind the curtain". Stallman offers a base for logical reasoning while Fox News offers a bunch of positions only good for uncritical acceptance.
