I'm not sure most of us do anymore - see my 1080p/24 inch example.

No one who has bought almost any MacBook in the last 10 years or so has had PPD this low either.

One can get by with almost anything in a pinch, it doesn't mean its desirable.

Pixel density != PPD either, although increasing it can certainly help PPD. Lower density desktop displays routinely have higher PPD than most VR headsets - viewing distance matters!