Enron was illegal but also a sham. The point is we have no evidence Nvidia's financing is a sham. It could be. And if it is, it's a huge problem. But the shammiest parts of what Enron did do not apply to Nvidia, which makes the comparison a bit like saying OP is Hannibal Lecter but legal while glossing over the fact that OP never murdered anyone but once drank red wine.

(Also note that illegal != illicit.)