Some roles are not 'neutered' by their commitment to various standards of neutrality, but strengthened by it.
Many journalistic organizations forbid their reporters from making political donations, or holding shares in companies on which they report. This is considered a good thing.
Public defenders take on clients without regard to the heinousness of their alleged crimes or the attorney's personal opinions of the defendant. This is also considered a good thing.
I don't think SOPA even in its worst form would actually 'neuter' Wikipedia. In particular, if the US government ever did censor Wikipedia with force of law, that would generate even more sympathy and uproar than a merely simulated blackout. And that might be the necessary test case to get the SOPA law struck down (by the courts) or repealed (by a later Congress).
That is, I don't think you can be sure that dropping one principle (political neutrality) in a dramatic gesture now will be better for the stated goal (defeating legalized censorship) than just diligently continuing to be a principled, NPOV source of reliable information.
Certain activists-by-temperament always want to politicize everything – "you're with us or against us, solidarity, unity, this issue is so important everyone must take sides!"
But society can often be more robust against injustice and oppression when some key institutions zealously cherish their duties of neutrality, and stay above the dirty business of politics, without applying any self-interest calculations.