do you really think that that BBC lying was a deliberate action of Great Britain government against your country? I think nobody thought that, so it wasn't banned.
In general you're mixing 2 different things - an operation of a foreign government on your territory and information content. Blocking the first is sovereign right while blocking the second is censorship and is a mark of dictatorship.
The RT operation in EU is blocked, while the content isn't - you wouldn't get punished for forwarding or retelling (on your own volition without any payment from Russian government for doing so) a content of RT propaganda contradicting official information of EU. In Russia BBC is blocked as an operation as well as its content - i.e. you'd get criminally punished for forwarding or retelling (again, even at your own will) a BBC content contradicting official [dis]information of the Russian government, i.e Russia does have censorship.