While the market is one thing to be focused on....
It is also important to note infrastructure deterioration, lower education standards, and overall deterioration of happiness. What I mean by that last one is, are you fulfilled and do you wish to spend more since you are happy.
Even more important is the savings rate. We dissave (spend more than we earn). The recent Fed actions have pandered to stock markets and made the return on savings (like the money you or me or a company would put in the bank) almost nil. That means the banks have no money, they go to the new discount window and borrow more money from the Fed. It's almost like the Fed is saying, "instead of raising the interest rate and having society save, we favor the idea of you borrowing it from us instead."
Personally I also think that each depression is unique. The Great depression was caused by a constriction in money supply, the own before you buy stock market, and Smoot Hawley tariff (protectionist legislation). This one (maybe a depression?) will be caused by a completely different set of influences.
Economists don't know as much as one would think. Each generation brings a new set of problems that are unlike any previously seen. It's almost like a science that lags behind the times. While in a situation, they don't really know, but looking back they can say, "Oh well this and this and this caused the recession."