You can’t service all of humanity if you allow the needs of politics to triumph over the needs of the people. And if you can’t service all of humanity, what is your relevance?
I don’t think that Twitter will fade out because, like Facebook, Twitter is too big to fail now. The problem is that these kind of measures (some might call them features) are now part of the process and not some kind of CIA tapping on the pipes. By doing automated self-censorship Twitter might be releasing a nest of wasps. That’s sad.