It was banned because twitter failed to appoint a legal representative, a condition of doing business in Brazil. Failing to appoint a legal representative is kind of like sticking your fingers in your ears 'nya nya nya nya' and hoping your problems go away. They didn't.

It was banned because it didn't follow court orders to remove illegal content from it's platform, yes. Whether the content was rightfully illegal, I don't know because I didn't see it, one side claims that it "was critical of the government" the other side claims that it "was inciting hate and violence".

Now I hope that we can agree that there are valid reasons to remove and ban online content, and from the news I hear about Twitter since it was bought by Musk I think the content was rightfully banned. Just knowing that Musk was against the ban is enough for me to believe so.