You are referring me to American style manuals. English per se, is not an American language. They took it, bastardised it and now use a slightly different form with different grammar and spelling 'rules'.

If you have read any of my longer postings on this forum, you would notice that I often use a hyphen (-) where I COULD potentially use a semi-colon.
Is it 'grammatically correct' or just 'common usage'?

The style manuals do not agree on a 'semicolon solution' because there isn't a 'solution' - and that's probably why the semicolon has arguably fallen out of common usage.

You suggested that the style manuals prefer to use a preposition, and given the choice, it's also my preference, as in :-
'from Los Angeles in California, from Nashville in Tennessee and from Beijing in China' etc, but that still doesn't make the previously cited uses 'wrong'.

The word 'ain't' is common usage but is considered 'slang'.

In your original 'complaint' about the way Caring used it, I agree with you.....

"The implication that suggests some of the highest ranked officials in some communist
nations have stolen the wealth from people is interesting; that especially in the
country where there's such a crackdown on corruption."

If the word 'that' is removed directly after the semicolon, he wouldn't be using it 'wrongly' - at least not as far as I can see.