The problem is apparently that some VCs invested in banks - and banks are about to be more heavily regulated. That's a good thing -- it will get banks implementing the backstops they should've had all along. I really don't mind if some VCs make less money than they'd hoped on their investments in risky banks.
Also, this $500B number is spread across the entire VC industry. And even then, most VCs have heavily diversified portfolios. Just for example, one investor in SVB was Insight Partners -- but their web site lists 800 different investments. They're part of that $500B number, but it will have very little effect on their overall portfolio.