I learned that polarizers did not work with autofocus and we had to get new "CPL" filters, 27 years ago. I even understand how they work and the nature of the light produced, which was a lot more effort in those days.
But I never found out why phase-detection sensors don't like linear polarized light. The old manual-focus ground glass screens featured "split prism" and a ring of smaller units, and we have no trouble seeing the effect with our eyes. The way light is blocked from one side or the other of the lens is not affected by polarization. The line sensors behind the split aperture must have some difficulty—but aren't image pixel sensors the same concept (cmos or ccd light measuring spots) (actually, I've never tried a linear polarizer's affects on a digital camera image so I'm just assuming it doesn't care).
What is it that doesn't like (linear) polarized light?