This post helped me realize the reason WeChat exists in China and nowhere else is because China has incredibly deep regulatory moats that keeps anyone from competing with its largest companies.
To be fair to Elon, I'm pretty sure the future you describe is not what he wants even if its the future he might get.
Well, Zuckerberg tried to add finance to Facebook and was turned down. If Elon tried to add finance, would they let him? Maybe under the current CEO.
Also, speaking of WeChat, here is a video where he says his goal is to "copy wechat"
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