Because...that's not what "banned" means and words matter? Like, there are countless shows and animes where the western rights holders haven't released a DVD or Blu-ray and there's no way to legally buy or watch these shows in the west. Does that mean that these shows are "banned"? No, obviously not. A ban means that some authoritarian institution decided to, well, ban people from watching it. That's just not what happened here.
If there is a considered opinion to not release content, then it doesn't matter whether that is because of a Governmental Agency, or the persons in the production company after they have had criticism or because they assume they would have criticism.
Your example of a company holding various rights but decides not to relase show A or B but release C instead would only make sense (in the context you've used), if there was a conscious decision not to release it based upon content that (however spurious) would be objected to, rather than them not getting round to release a series, although if they purchased the rights only to sit on the content and not make it available, then this would also be as objectionable as it being banned by the Government.
I am aware of the definition of the word, but the fact that pressure can be applied to stop the release of content due to parties other than governmental agencies makes the argument 'well everything's cool, content has not been made available, but this is not due to a 'ban' from the government, so that makes it ok' academic.
Also, perhaps I needent mention this, but what the heck, it's not like a words literal definition can't be stretched over the years.
