Plato? YES!! CdM has it! And what he now has is possession of the Platonic ideal of a baton. Those early shots in the dark really looked like they might hit.
Anarcho-syndicalism? No. A work of writing? No. Recipe? No.
A clarification: I believe my "yes" answer to "Created by humans?" is the least misleading but I suppose proponents of this -ism might dispute my answer.
Idealism? No. Anti-? No. Spiritual? Another interesting question. The best answer is No, though I'd caution that "spiritual" admits of multiple definitions. The AOTC is spiritual-adjacent, however Crackpot? If you presented the AOTC to random people on the street, most would agree with that descriptor. If you asked those with more specialised knowledge, some would certainly still agree; the majority would disagree with the AOTC without (I think) necessarily being so pejorative. I hope that helps. :)
Veganism? No. AI? No. (*a few glances exchanged in the audience, but no actual applause*) Dianetics? No. Geography? No. Geology? In some sense maybe Yes, but that's unlikely to be helpful. Related to Art? No.
We know that this is an ISM and refers to to something that was invented by humans, and that's about as far as we've got. We do know that it doesn't begin or end with p, c, or anti. It has nothing to do with geography, geology, art, literature, or astronomy. It's not veganism, idealism, creationism, or dianetics, nor is it named after a person. There is a possible tenuous link to religion/spirituality, although all the guesses so far have not led anywhere. Normal people will think that the AOTC is crazy, those with more specialised knowledge will think that it doesn't work, although it still has its supporters.