Freedom of press applies to the government silencing the press. Your situation is more like if you were writing a column in a newspaper - and then that particular media stops liking your writing for whatever reason. Freedom of press won't help you in that case, but you're free to go make your own platform - that's what freedom of press covers.

I don't use Twitter but I run a small platform (oldschool forum) and without shadowbanning it'd be impossible to curb the bots. They immediately react to a classic ban.