One more clarification. B’s recap stated “those with more specialised knowledge will think that [the AOTC] doesn’t work”. I’d say,rather, that they’d think it isn’t true.

1.6 billion? I think that the adjacent spiritual/religious concept quite probably has more than that number of adherents. The AOTC is a more technical notion (and term), which would be unfamiliar to (most of?) those adherents. I think. The adjacent spiritual/religion-adjacent concept might be a helpful route to the answer.
Governmental? No.
Associated with a particular group? For the AOTC itself, I'd say No. But the adjacent spiritual/religion-adjacent concept is certainly associated with various identified groups.