That important function is severely impaired by fiat debasement. When people use stocks to store value, corporations get basically unlimited money because they can use stock sales as a funding mechanism. This means the stocks are making the economy less efficient, as people allocate value to companies that their customers don't value. Prices of goods and services are a voting mechanism for the market to say, "make more of that!" If it sells, you're providing value. If it doesn't sell, the company needs to adapt or disappear so that other ideas can use their assets. Stocks allow corporations to bypass this competitive feedback, and thus inefficiencies build up in the economy. If fiat wasn't debased, it wouldn't be a problem, because value would be stored as money instead of stocks.