That page gets it right in the "Definition" section saying the term is basically slang derived from the StG44 and that to be considered an "assault rifle" it mu

That page gets it right in the "Definition" section saying the term is basically slang derived from the StG44 and that to be considered an "assault rifle" it must be select-fire. Those are Class III weapons in the US and already very restricted, assuming you have enough disposable income to buy one and find a seller. The example given in the post has nothing to do with Class III weapons, so the term is used improperly, that is my point.