Although I agree with you that fundamentals will eventually win out..... You can see in Consumer Credit that has increased by 30% since 2010 and Salaries has been flat... I would also say the number of workers have increased by 15% which gives us a 15% increase debt over income....
Now debt has been increasing for 6 years, and families are more in debt on average than every before.... Something has to give.... Falling stock prices could mean slower spending and we have the snowball effect... A new technology that everyone wants could increase production and more spending.....
I do think we have more downside risk, but the time frame is long to make real money on these fundamentals unless your horizon is 3 to 5 years for trades....
In the meantime GDP is trending down, as long as that trend continues eventually the piper will be paid.