Look at this paragraph from the article:
One of those irrational reasons may be simple habit. Something strange happens when people retire, Browning says. All of a sudden, they’re not getting a regular paycheck, and that makes them scared to spend. Goals set before retirement are abandoned, along with pre-determined spending plans, because retirees are terrified see the balances on their retirement accounts drop even a tiny bit.
What's wrong with someone, like a financial planner, reassuring a couple that yes they can take those vacations they always dreamed of, yes they can pay for their grandkids' college tuition, yes they can make a substantial donation to that museum they love so much -- here's the math showing that it is likely to be okay?
The article implies with the talk about "training people to spend" that other people should be concerned about this, but doesn't say why. I'm not really seeing it. It's not like the money supply is fixed. There are other ways to grow it if the Fed were willing to do it.