Their economy is bigger than the entire European Union. They wield unparalleled influence in Asia and run much of Africa. The US is deeply invested in China. Regardless of their consumption (which is significant) - if they were to experience any form of major correction or devaluation, we would most definitely feel it.
i'm not saying we wouldn't feel it. i don't think it would have nearly the effect as the us, japan or EU.
the economy is bigger than the EU but there are also a billion more inhabitants. the EU, comparatively, is hardly larger than the US and includes a handful of basically developing countries. the economy is bigger bceause there are more people working. if they lose jobs it would be felt inside of china severely; outside, we might see some price fluctuations and there is a chance they would be short-term. the broader impact would probably be staunched by jobs onshoring, or moving to other developing countries in the region. we aren't talking about a bastion for sales by apple, google, and facebook. we're talking about cutting the supply side for those companies, but the truth is that they've been moving out of china, anyways.
as for influence in africa... even if their influence is unparalleled we're talking about the least productive continent in the world. it barely registers. the bigger concern is how china has moved to wield influence over SA. but, given the slowdown that could wane (for instance, will the money be there for nicaragua?)
your claim about influence in asia is simply false. the appendage of china which wields the most influence is hong kong, and it isn't even clear to what extent china wields influence over HK. the rest of asia has a mostly antagonistic relationship with china (See: territorial claims against Malaysia, Vietnam, Japan and Taiwan). China is even alienating communist countries (See: Vietnam). meanwhile, the US wields great influence over japan (second largest economy in asia). and Indian-Chinese relations are lukewarm at best (and that's generous). korea is also oriented westward. the country china has the most influence over is north korea. good luck with that.
china's economy has grown at an astonishing rate over the past two decades. but its institutions haven't caught up to the rest of the world, there is still an enormous impoverished underclass, the people, even well off, remain fairly oppressed and it simply doesn't wield the influence outside of its borders that the size of its economy suggests. it has tried to exercise that muscle, but has only started doing so in earnest while the wheels, internally, appear to be coming off.
