This has nothing with global economy, its just a bad day day might turn into a bad week for trading, but in the general people does make money no matter the market cap at all, crypto is different other investments, with that said dont worry with those, because crypto started with few buck and now is worthing bilions.
Since we are seeing big time investors may be there is a link between global stock market and the alt coin market,people might book their profits in the alt coin market if they see a heavy correction in stock market so that they could buy some stocks at a lower price and average the entry point,who knows ,things are changing here as we are seeing huge investments coming into the alt coin market.
The global equity markets are driven by institutional investors. Big pension funds and hedge funds pour in billions of dollars into equity markets. The investor base for crypto, especially marginal alt coins, is very different.