Governments can endanger citizens’ freedom because they have monopoly power within their respective territories and there are enormous burdens on switching to a different government. By contrast, users could freely switch to a different search engine or video-hosting site if they were dissatisfied with Google or YouTube. (Currently, AFAIK, the main competitors to YouTube exist because of opposition to YouTube’s anti-porn policy; but if it had other widely objected-to policies, other alternative sites would gain ground likewise.)

P.S. In addition to this misdiagnosis, Weitzner’s solution is flawed as well: “someone in government” *did* have the right (and IIRC the statutory duty) to inspect the black box economy, but failed to effectively exercise that right because of government-corporate entanglement. There’s no reason to suppose the same wouldn’t also happen to government supervision of search engines, if they were corrupt enough to need it. If you want truly effective supervision it has to be carried out publicly by the community of users.