Additionally, the intervention Twitter seems to have chosen here wasn’t actually to silence the user (who happens to be the current President), but to mark/anno

Additionally, the intervention Twitter seems to have chosen here wasn’t actually to silence the user (who happens to be the current President), but to mark/annotate with a fact check label, which is essentially responding to speech with more speech. That’s entirely compatible with even far-reaching 1A readings and robust philosophical perspectives on it. And in fact, Twitter’s civil leadership policy has been allowing such users (including Trump) extra leeway. The fact that Trump is mad about this shows that what he’s concerned about isn’t his own freedoms of speech are being impinged on, but that his freedom from accountability in discourse might be threatened.