I don't follow. Why draw a distinction between the "mode" of speech, and its "content", and what exactly is the difference?

With apologies, it sounds like a "no true Scotsman" position, where censorship is only real when it bolsters one side of the argument.

What’s an example of free speech being violated now (in the USA debate at least) that’s not about violence? Just curious what you think should be ok to promote without restriction that you think is being curbed.

As the article points out, neo-Nazis have not been allowed certain platforms for a very long time and would get "cancelled" if their views were known. That is content of speech.