This doesn't work when the economy is already close to full employment, full consumption of available energy, and full capacity on critical parts like ICs which it's hard to expand the production of. Without any excess slack to increase production in order to fill that increase in consumption, it just has to come out of other people's consumption through inflation reducing the value of their wages.

It's also not at all obvious that this is better than someone just investing a bunch of money. After all, the way investments ultimately make money is by supplying people with what they want at low prices, which means that investment money floating around can lead to innovation which supplies people with more stuff using less resources, increasing the amount available for everyone can buy with their wages.

This falls foul of the glassmakers fallacy - money invested in a portfolio will still be used for something, so it is generating economic activity.