Twitter's censorship was wrong, and those countries and ISPs censorship would have been wrong as well. Free speech is a human right and censorship is immoral.
Twitter (and Facebook and any other online site) has Terms of Use policies that all customers must abide by if you want to use their platform. If you don't follow their rules, they can remove your content or your account. That is their right since it's their platform and you agreed to their rules when you signed up. If you don't like their policies you have the freedom to not use their platforms.
This has nothing to do with what I said. When I said it was wrong, I meant in a moral sense. Freedom of speech is a human right, which is ensured in the United States by the first ammendment of the constitution. Twitter is morally culpable for its censorship.