an organized attempt by a group of people to defeat their government and take control of their country, usually by violence:
J6 cannot meet such a burden since it was not an organized attempt and it certainly wasn't violent in the way that a real move to overthrow the government would be, only violent in the sense that any disorganized protest can be.
... And while some people can toss around the word insurrection, you notice that there is no serious charge against Trump on this, because there can be no charge, since he said nothing nor does any other evidence exists which show he incited anyone to any illegal act, let alone an attempt to overthrow the government. This is only possible through assumption & interpretation of what happened that it was even an 'insurrection.'