The New Yorker's James Surowiecki argues that Elizabeth Warren is in fact a friend of capitalism:
The core principle of Warren's work is also a cornerstone of economic theory: well-informed consumers make for vigorous competition and efficient markets. That idea is embodied in the design of the new agency, which focuses on improving the information that consumers get from banks and other financial institutions, so that they can do the kind of comparison shopping that makes the markets for other consumer products work so well.
When you look at the rash of subprime loans that triggered the financial crisis, the theme was financial institutions competing with each other to dupe the most customers, not provide the best product. And not just home-buyers but also the other banks and consumers who bought the securities made up of these bad loans. Though at first the financial industry seemed to have no idea what they were doing was dangerous, even once banks knew that they were selling bad securities, they kept on selling anyway. The crisis should have made it clear that capitalism really only works when people at all levels of a financial transaction – from homebuyer to investor – actually knows what they're buying. Otherwise, there's a big crash.
Surowiecki makes the point that the CFPB could actually strengthen the financial industry by helping borrowers make good decisions, which then preclude huge crashes. But almost 3 years after the 2008 crisis, banks' profits are higher than ever while home-buyers are still struggling to keep their homes, so Wall Street never had learn this lesson. Politically, it would be nice to see Democrats using capitalism and competition to promote their policies, rather than getting slammed for being anti-business and anti-free-markets when they aren't. Sadly, it's easier to claim that all regulation is bad than to make the nuanced argument that some regulation actually guarantees capitalism's success.