People need a reason to route.

With the housing bubble, it was because people owned multiple homes then struggled to pay two mortgages as economic conditions degraded, and banks were willing to absorb losses if the homes were sold below the cost of the mortgage.

What is encouraging people to route from the stock market? Bond yields aren't high enough yet to encourage people to retreat from stocks, and there's no other alternative investments. Plus, so much of the S&P is held in 401ks. And I agree, economic hardship is not widespread enough for people with significant investment holdings to start selling them off to live. Those who are struggling are those who used to be struggling too (thus, no extra money for investments).