While more on the parent side of the age gap of things now, I know at least five offspring personally who do this willingly. It is a nightmare to me, moreso the fact that it’s basically impossible or was the last time I looked to find ways to do it that are foss.

But the point is, probably more people do it than you expect. This place is a selection bias, most people genuinely give no rats ass about their privacy, and, to the shock of many, trust their parents and like the safety net.

There are certainly secure privacy focused approaches they retain the agency of both parties which could exist. It’s a very real niche.