In fact, the very reason why polarized lenses are so effective is the reason why they are not recommended for pilots to wear. Polarized lenses diminish glare by absorbing and blocking incoming horizontal light, while allowing in vertical light.
First, this effect can cause issues in the cockpit in regards to the aircraft’s instruments. Polarized lenses can reduce the ability to read instruments that already incorporate anti-glare filters. Additionally, they interfere with the ability to read LCD instruments, which emit polarized light.