Arguments Against The First Amendment

I believe that the first amendment should be accepted no matter the institution being publicly or privately owned. After reading the CNN article I was left wondering what the point of having an amendment promising freedom of speech if it's only conditional. I believe that if we have an amendment promising our freedom of speech we should be able to speak freely regardless of their surroundings. I do believe that people shouldn't use the first amendment as a way of spreading hate so not being able to make threats in places like an airport can be helpful. The article skimmed over where you can and can't use free speech and blurry areas. The article stated that if a company like twitter bans you for using hate or threats that you can't take