They enforce on some illegal actions on the internet, child pornography, slave trade etc. etc.. Of course that is mostly only on the surface net, all the deep net stuff is much more complicated to root out.
But other than that, just look at this site, we can shit on and lie all the way to sunday about government and government officials all day, and the site is still running. So it is far from the 1984 scenario some people are delusioned is crushing down on them every second