The short answer: cheap exports. However, that comes at a cost of making it expensive for Chinese travelers on heading overseas especially with EU, UK or US since they will need to pay more to exchange Euro / Pound or US Dollars when converting directly from RMB, since the Yuan is not strong against those major currencies.
Despite China having the second largest economy, their own currency is still weak against GBP, EUR & USD. Even though China is cashless for the most part, they still print bank notes (which are shit value) when you convert them as it's basically "pocket change" (so Western travelers have higher purchasing power than the Chinese):
By contrast when you exchange GBP, EUR & USD for Yuan (RMB): you still receive more than in their currency than a Chinese traveler would when they exchange RMB directly for GBP, EUR & USD when they're in a Western nation:
It would mean for a Chinese traveler, they'll be spending A LOT more money in the West (expensive for them due to lower purchasing power) than the reverse to an American, Brit or European when it comes of as "China is so cheap" flex just because they possess currencies that are worth more at face value.
Not to mention a "weak" dollar isn't bad.
Chinese money buys less in the west, because everything costs more in the west
China has incentive to keep it that way, because most of what is sold in the west, comes from China.
If things cost the same in China as the west, then China couldn't sell things to the west cheap enough to undercut their own manufacturing. Which would mean the loss of all those jobs in China and the corporate profits.
OP just thinks it's a bad thing, because they don't understand it's intentional.
China wants things to be cheap in China, it shouldn't be a difficult thing to understand
It also means that Chinese workers are underpaid.
It doesn't. Because they live in China.
and Chinese buy foreign products too.
They would be more underpaid if their dollar was "stronger"...
Like, you get that, right?
There's no way to ask this question that's not condescending, it should be incredibly obvious that if they were paid more, it would both raise domestic prices, and prices of everything they export, raising western prices.
And we'd end up right where we are again, and you'd recommend again with a straight face that raising their wages would fix it....
Oh sorry dollar, I thought you meant RMB, because you wrote so much about China, and just miss wrote that. Also most stuff is not made in China. Share of global GDP of China is like 20% or so.