> it can't be that difficult to port whatever code to whatever platform if 100s of millions are in question, or is it?

300M hires a lot of engineers. Maybe the fact that they are buying instead of building tells you how hard it is to build and how strong a moat Nvidia has.

Musk has publicly said that the true test of their own training hardware efforts is if the ML team switches to it. I.e. it’s a software, not hardware problem.