Perhaps like the old Soviet economy, where everybody had a ton of money in the bank, but nothing worth buying?
There would be nothing worth investing in either, because no one would spend their money, just "invest" it in now worthless entities.
Thank goodness for the folks out there who shop till they drop. They may be spending their retirement, but they make the world go round for everybody else.
Where did you get the idea that soviets had tons of money in the bank?
As far as what would the economy look like if everyone saved enough for retirement? How about a federal budget of half what it is now and ALL citizens having larger paychecks both because of lower taxes and because of greater business activity.