It's intended to cripple our god-given right to pirate stuff with the internet.
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The internet obviously doesn't want this to happen. However, the internet is an idiot and can't think of any real reasons to oppose this, so that's why you're just hearing a bunch of aimless ranting.
I don't like it because I'm cheap. Forming a more morally defenceable argument is an exercise I will leave to Americans, who's opinion congress might plausibly care about.
I will say I think it benefits corporations more than it benefits individuals, which I don't think is the right direction for any government to go in.