Fair enough to have a debate upon what "insurrection" means. I suppose in the end, that will be the crux of the case with Trump, and SCOTUS may take advantage of that and opt to muddy the waters further, devising some opinion to state, in effect, "we don't know that he engaged in insurrection" and on those grounds overrule Colorado.
From my personal perspective (and just my opinion) there is nothing remotely vague about the word "insurrection." It really is one of those "you know it when you see it" sort of things. Dare I give the analogy of Justice Potter Stewart when pressed to give a definition of pornography, and he said "I know it when I see it." Indeed. I knew it when I saw it live on TV on Jan 6th. I felt the horror of it. I saw the footage of the woman shot, and I saw her bloody body taken out on a stretcher.
More to the point, however, I knew in advance to watch coverage of Jan 6 because I knew something terrible was going to happen because I knew that the response to the Trump tweet to "be there" and "will be wild!" was online chatter among his supporters about how one could get guns into DC.
Insurrection? I know it when I see it.