Yes, those innovations are critical, but those central concepts and the legal mechanisms that make them possible have very little to do with what much of Wall Street does, which is inventing financial devices and arbitraging the everloving crap out of them.

I think the point of "the world goes on without Wall Street" is that banks and stock markets will still provide speculative capital to expensive ventures whether or not high frequency trading is around, and agriculture will still grow and sell food whether or not hedge funds are buying and selling futures.