The simple answer to these situations is usually that it's not the same people complaining in both instances. I see similar things in places with anonymous posting where people assume everyone was in agreement on x, then later they hear something different and try to frame it like a flip-flop or a gotcha. People are never all in agreement.

To add to that, often no news is good news, or rather people won't bother posting about how they're glad minors can use social media freely, but once restrictions are in place they will quickly complain (because they prefer the old way).