That Communist China has assumed this role in global affairs

Just because Xi went to David to beg for continuation of global trade (so that China can continue to use export-oriented industries as an economic crutch) does not mean it's assumed any role. In fact, China is far more protectionist than the U.S. and shows no signs of changing at this point.

In my view, the sheer weight of numbers in China’s population lends credence to the argument that China’s integration with the wider global economy and population will continue to increase.

You provide no actual link between population and global integration. The CCP has been able to keep China's population fairly isolated from the rest of the world through protectionism and control of the Chinese internet infrastructure. There's no reason to assume China's large population can prevent the CCP from keeping it socially separated through propaganda and censorship.

Here's the most important question, though: even if China were to become more globally integrated, why would I care about teaching them Chinese? To begin with, Chinese won't replace English as a global language. Anyone who thinks otherwise is living in a fantasy. Furthermore, what's the point of wasting money on your fancy daycare if they're just going to stop using Chinese once they leave? It's far better to teach my kid Spanish than Chinese.