Demographic cliff on a scale not seen: yes Japan is going through one now, but China's is simply unprecedented in the sheer numbers
Authoritarianism: China is rolling back free market reforms, centralizing power under Xi
Finance: China has a real estate and debt bubble at the regional government level.
War and aggression: China US relations are approaching cold war levels and a Taiwan invasion seems likely. Four years of trade war is imminent.
Depending how it plays out, any one of these is trouble for offshore manufacturing in China. I suppose collapse is a strong word, but it is stupid to rely on Chinese production both for a company and in terms of national security.
Zeigan has been singing this tune for a decade, but recently there are many other geopolitical talks I've seen repeating each or all of the four issues I've listed above, and the demographics aspect is inevitable at a minimum.