> A shrinking, aging population would fix this problem. The demand for labor will go up, the supply will go down. Bad for the investor class looking for profits, good for reducing economic inequality. People will be able to profit from labor again.

An economy exists to fulfill human needs of various kinds-- making stuff, providing services, etc. Old people intensively consume (medical services, etc) and don't produce anymore. Getting too high of a ratio of old people therefore has some impacts beyond equilibrium labor prices.