> Other countries do not even have the concept of freedom of speech/assembly embedded into their founding documents.
as it was clear that the author hadn't done any research on this - many countries explicitly or implictly have these in their founding documents.
In short, the important distinction is not that it's embedded into the founding documents, but that we do not place the limitations on free speech that other countries do.
i.e. places like UK, germany, france - while they may have the phrase "free speech" in their documents, the limitations put on it are extreme enough that they're basically referring to a totally different concept.
So, it would be more accurate to say that other countries do not share our concept of free speech, in that ours has _very_ few limits put on it.