A couple of things here are ironical.

If the share is expected to drop only by the %age of revenue miss, you won't need a stock market. The price would've been fixed and you can buy it like any other goods.

Apple only tightened the user control of activity tracking and this resulted in all the social media stocks tanking. This shows how much the violation of user privacy means for these stocks. Each big corporate talks big on the need of privacy but does exactly the opposite.