Consumers have been capturing an increasingly large share of economic growth, as american style efficient retail speads globally and prior protected local markets face increasing, global competition. The fight to retain share and these forces are squeezing profit margins, and hence equity returns.
The next decade will be great for economic growth, consumer value, and companies with sustainable competitive advantages, but bad for local job and wage growth, bond returns and corporate profits overall (IMHO).
Assuming the global trade markets and social structures stay stable, Mustacians will do very well in this climate. Just don't quit at 30 assuming 7%+ returns will fund you for life. I think it is safe to assume that plenty of tech driven spending efficiencies will help us make up for the lower average 2-6% returns though. For example, our solar deal rocks, our heater/windows are much more efficient, our Prius driving cost per mile is great, organic local produce never more plentiful and reasonable, etc.