No one censored her. Her opinions go against what the Olympic movement stands for and expect the participants in their games to stand for. What she did and said violated the Olympic values, so the Greek committee banned her.

That's one thing to whine about individual rights, but there's no fundamental right to participate in the Olympics. The event and its organizers stand for certain basic values and they promote them (and to make it clear, those values don't exactly include xenophobia and racism). They're perfectly within their right to ask of those wishing to participate to their event to adhere to those values and rules or else abstain competing in olympic events. It's not like athletes don't know what the Olynpic movement stands for and ask them to stand for.

Freedom of expression doesn't extend to facing no consequence whatsoever for the opinions you expressed and how you did it. One might well have the right to publish articles demeaning, say, to feminist groups, but you just don't go complaining if one of them one day invoke this to refuse you a job. Try getting a job with a catholic organization if you're publicly a pro- aborption militant. One might have the right to express xenophobic views, but that person shouldn't expect an international organization that officially promote the opposite values to welcome her at one of their events with open arms... or that Greece where there's a highly xenophobic party that attracted a lot of bad international attention last spring would be too keen to risk an international scandal by letting a woman who makes xenophic jokes on Twitter represent her.