Yeah, finance can be messy for those who just get into it at the smaller to medium scales but who only have some experience in analyzing investments at the micro scales without really understanding the macro scale economics behind it.
If the stock market responds to sales by spooking investors who then sell at lower prices, then the market cap was always a scam. Exchange value of the collection of stock shares for the shareholders is actually not last_price * outstanding_shares but a much smaller amount that exponentially decreases as people sell out.
The use value for the company too is not represented by market cap because short term speculators aren't going to be around long enough to allow you to realize those investments as assets, and anyway there's a large contingent of shareholders who either don't understand or don't agree on company leadership's decisions, so the true value is much lower than depicted.
It's basic economics. Value is what can be done with the set of assets and the collective beliefs held about them, not the projection of such from some pseudo-equilibrium state.
However, big finance depends on you either believing their falsehoods or getting out quick enough that the grift is completed so that average Joes are left holding the bag. They're not on your side, so why continue playing by their rules?