Pixels very much exist in hardware outside mobile. Microsoft’s clear type even exploited the specific layout of color channels in discrete hardware pixels. Mobile displays are all over the place, but most other displays use standard RGB layouts.
You've described the exact problem. Sub pixel rendering exploits the fact that most display pixels aren't discrete logical squares.
https://en.wikipedia.org/wiki/Subpixel_rendering
You've described the exact problem. Sub pixel rendering exploits the fact that most display pixels aren't discrete logical squares.
https://en.wikipedia.org/wiki/Subpixel_rendering