So if you were his right-hand man and expert on China (Munger style) you'd advise Mr Buffett to sell out of Apple completely?

No....
Because I'd be right hand man to Mr Buffett rather than anyone else, so I would defer to his judgment.
Jockey reasoning.

It's not just because he's famous, or his reputation for good portfolio performance.
Specifically, I am sure he has thought about this very issue, hard and often.
For example I would be very surprised if he hadn't read that specific FT article and pondered it at length.
And I know he has no hesitation to dump all of a giant position promptly if he no longer feels comfortable with it for any reason.
So if he still has the position, he's still feeling the love.

True, I doubt he is the most world's most insightful thinker on geopolitics.
But he is famously risk averse, and famously concentrated in the US because of its very predictability for owners.
If he is making steps that seem not to be in keeping with that, I am sure it is only after careful consideration of the upside and downside.

I believe his record stands: no portfolio he has managed has ever had a position which ended with a realized loss of over 1% of portfolio size.
Gosh, imagine how my portfolio balance would look if I had managed that feat over the years...

But I am not Mr Buffett.
So I am not making that same decision for my individual positions.

Jim