To be fair though, that never was much of a conspiracy. Maybe in the United States it was but in the rest of the world I don't think people believe the WMD story, rather, we believed the UN weapons inspectors' story.
I've told and convinced plenty of anti-vaxxers about the magical secret way our body naturally produces antibodies if we expose our body to dead versions of a virus (or, now, things shaped like that virus). They like magic, secrets and nature, they do not like the word vaccine.
I do the same with the word conspiracy, "That is a secret plan by a group to do something harmful". It rolls off the tongue.
I think that's interpreting the term "conspiracy theory" more broadly than it's typically used. IMHO, colloquially it pretty much only refers to outlandish theories, based little to no actual evidence, and usually requiring a conspiracy so impossibly large and impossibly well executed that it beggars belief.
I don't think the idea that Jack Ma is being targeted by the CCP is just a plausible theory, not a conspiracy theory (in the colloquial sense). You have a group with the motive, means, and MO to do so, you just need to find the proof.
Which is the definition of a conspiracy theory. Words have meaning and this is a technical term; and altho it is common knowledge that it is being used as a smear word, this doesn't mean we have to play the same game here as well.
There is also no reason to pretend that the colloquial usage of conspiracy theory is more than opinion.
That being said: Your explanation makes more sense to me. It is often enough to anger the wrong person to get a bad treatment (well, even assassination). And looking at history this is exponentiated in dictatorships, where power is concentrated on few ppl, who can act with impunity.