How can a rich person ever claim that a poor person would be better off with their wealth and not come across as absurdly patronising?

You're giving the standard capitalist party of line, of course - growth is good, etc.

I'm sure there are people in China and Taiwan who'd agree with you.

But they may not be the ones in the factories doing the work.

Your mendacious implication is that 'riches' are a one dimensional good that Africans either have or don't have.

In practice what usually seems to happen when Westerners turn up promising riches, is that the riches are perhaps not made as widely available as they might be.

Anyone who questions this too aggressively will indeed be killed or tortured.

And perhaps you're not aware of the new anticapitalist movements which aren't interested in G20 confrontations or grandstanding, but are interested in promoting sufficiency rather than greed as a core social value, and which see the capitalist West as an inherently dysfunctional and insane place no matter how rich the people appear to be.