I don't think it is that obvious because, at least me personally, I haven't seen any evidence of this. Now there are websites that are built around reducing visibility of unpopular opinions (like this one and Reddit), and elevating popular opinions (like Twitter), but I don't think it's fair to call this censorship. You can't join websites where opinions are judged and then complain when they're not judged your way. By that logic, every time a candidate loses office, they've been "censored", which isn't an honest application of that term.
The only times I've seen posts stricken is when they're damaging in some way, like vaccine misinformation or voter misinformation. It just so happens that one side seems to indulge in a couple of those categories.