Blocking RT has little to do with the opinions spread by it (though highly correlated for a variety of reasons), other people in Europe are allowed to say and spread the same ideas without any repercussions. It is about fighting the intelligence operations by a country that is quite literally invading a bordering allied state. RT isn't being blocked because it spread ideas that are contained in some EU law to be illegal and dangerous opinions, they are being blocked because they are owned by the Russian state.