Too lazy to read the article, but this was a thing in Russia for a long time. The USSR falling apart in the 90s correlated with a bunch of special forces coming back from Afghanistan and then Chechnya. They had no jobs and crime rates were high, so naturally private security companies popped up. Naturally, body guard schools popped up.

I didn't read the article, but I watched a documentary on the Chinese companies, and it seems like they are far closer to the security guard than the "any threat, anywhere" type deal.

Regarding Blackwater and its equivalents, there is a merc company called "Wagner Group" in Russia that recently attacked an oil field in Syria held by pro-US rebels. The US hit them with artillery from a MEC position, and then fixed-wing and AH-64 CAS ran train on them for four hours. The US and Russia initially denied any direct US on Russia contact. So, it seems like Russian "military" PMCs are more expendable, deniable spam when compared to BlackWater/Academi/whatever they are calling themselves these days.

That's not to say Russsia doesn't have the capability, but they prefer to keep their "PMCs" as black units directly under FSB control, a la "rebels" running around Ukraine with radar-controlled machine guns, taking out helicopters on take off, etc.

To tie this all back to China - they haven't shown themselves on that level yet to the best of my knowledge.