Now to get to the actual economics:

Investing in the productive economy hasn't yielded a positive return for the last ten years

Given stock price trends I can't see how this is true. Can you elaborate? Even Treasuries are yielding 3-odd percent in the face of 2-odd percent inflation.

unless you want all behavior to shift toward consuming all real resources immediately, including "seed corn", you have just as much an interest in seeing an economy strike a balance between present an future consumption

The wealth of a nation is not some fixed quantity; it's its aggregate production of goods and services. There's not anything we can "run out of" that's required for people to trade, barter, etc. Am I missing something?

Sure, there are finite resources we could run out of, like oil. But attempting to restrict the total size of the economy in an effort to conserve those particular resources seems awfully suboptimal. (It also seems doomed to fail in an economy consisting of humans). Better to attack those particular resource usages through taxation, policy, subsidizing alternatives, etc.

Try to bear with me; and I will try to remember where I am. This is the first time I've met a hard-money advocate on the Internet who also [presumably, given our venue] cares about map-territory correspondence.