In light of what's been going on in the last few days the entire concept of "freedom of speech" and how that works with private companies has become a hot topic yet again.
Twitter, Facebook and other tech companies all have terms of service. If you breach those terms the companies can suspend or terminate your access to their platforms.
The US has strong freedom of speech protections, but they're not without limits. The example often cited is that you cannot yell "fire" in a cinema (unless there actually is a fire of course).
XKCD's comic gives a very simple explanation of the key points of this:
Does this mean that Twitter should have suspended Trump's account now? With only a couple of weeks left in his presidency it's a bit "convenient" that multiple tech platforms have now decided that Trump is in breach of their terms of service. Yes this week did see the riots on Capitol Hill, but Trump has been using his social media accounts to spew hatred and lies for a long time. However in light of the violence on Capitol Hill there is a strong argument that he went too far.
Mike over at TechDirt is one of many to write about this in a clear and articulate fashion. Go read it.
It's not a simple topic and it's not clearcut all of the time. Many of my friends work in the legal, safety and abuse teams with some of the largest technology companies in the world and I know they struggle with these kind of issues and questions on a daily basis.
Other friends of mine spend their days on the policy and more abstract areas of technology. I suspect several of them will write pretty cogent pieces on the topic like they have done in the past.
But the President of the US is not a "victim". He's able to walk into the press room of the White House whenever he wants and the world's media will report his every word (or at least the cogent bits!).