Bubbles are usually caused because people think to sell to a greater fool down the road and at some point there are not enough fools to sustain the upward price

Bubbles are usually caused because people think to sell to a greater fool down the road and at some point there are not enough fools to sustain the upward price momentum. At some point all the fools want to be out and the price collapses. Crypto going from a 3 trillion market cap to 1 Trillion in the space of a few weeks is a great example of that. Technology stocks are mostly different with the exception of some startups that are valued based on user growth instead of revenue growth. Users are not customers though, and customers are the only real sustainable source of finance. There are a lot of technology firms now that are financed by their customers so even if there is a full stock market meltdown in tech stocks, you shouldn't be afraid of unemployment but salaries will adjust to the reduced competition from VC-funded startups.