Right. Stocks and other assets are used as collateral against loans. The loans give them liquid cash, but they're not taxed on this.
There are probably a bunch of solutions to this, but the ultra wealthy enjoy this system so changing it has well financed opposition
It's really hard to get people to suffer mild inconvenience when they don't emotionally connect with the benefits.
Most of facebook's evils are remote and impersonal. Seeing your cousin's baby photos is real and at hand.