That’s not the point. The issue is that loaning/investing to a client so they can buy from you conflates your investments with your revenue.

It may be fine, or not. It it has been a frequent type of manipulation to obfuscate the real accounting situation.

Yeah, it's basically creating the illusion of demand and revenue. Lots of fraud in the past relied on companies "investing" into companies which then bought from the investor. I'm not sure to what degree this is happening now, though, and to what degree this is benign.

People are investing because if Nvidia are essentially buying shares with graphics cards then they're motivated to make this stuff work. If the invested in company's share price tanks, Nvidia loses out, and I imagine quite a few people are willing to win or lose alongside Nvidia.