I see it more as leveraging (and also diversification). NVIDIA gets a pile of money. Rather than sitting on it for no purpose NVIDIA doubles down on AI success by purchasing ownership in AI companies that use its products (although not exclusively its products).

This way even if some other hardware eventually powers AI, NVIDIA will still benefit. The only thing needed for NVIDIA to continue doing well is AI as a whole to continue doing well. Which is almost given.

The fact that well financed NVIDIA customers now buy more NVIDIA products is additional benefit. So what NVIDIA is doing financially seems like a no-brainer.