An alternative perspective: https://meltingasphalt.com/wealth-the-toxic-byproduct/

'Hoarding' money doesn't consume any real resources and therefore one person saving can't really deny anyone anything that exists in the physical world.

There are some complex questions of whether it causes more or less resources to be allocated to the poor. It isn't a simple as branding someone a hoarder.

Indeed, a complex experiment has been running since the monetary systems moved off the gold standard that suggest the less people save, the more unequal society becomes to the benefit of the wealthy. There is a reasonable argument that when the middle class 'hoards' money it increases the access of the poor to things they need.

Damn - I'd better stop hoarding money in my 401K too!

Not spending it means not competing with other people for current consumption, which means lower prices for everyone else.

If the money is parked in property or some other rivalrous asset, then you're more correct. But not for money.

She is saving it for her kids.