I've seen trump supporters use terms such as "discrimination" and "freedom of speech". Such terms may appear in federal law, but a private corporation can make their own rules. Trump agreed to the rules when signing up for the free service that he greatly benefitted from. If he gets banned for not following the rules - just like tons of average Joes have been - it's called EQUAL TREATMENT in fact, not discrimination.
Regarding freedom of speech, again the private platform gets to choose and moderate the content as they wish. If I create a discussion group where the topic is dwarf ponies, and someone wants to chat about what anal lube Vince and Vissy liked the most instead, hell yeah I'm going to moderate and remove the content.