IF the laser is (linearly) polarized to a fairly high degree (not too
difficult in practice),

and IF the pilot is wearing polarized sunglasses (readily available),

and IF the laser is physically rotated (about its long axis) so that its
direction of polarization exactly matches the linear polarization that
is blocked by the polarized sunglasses (has to be done carefully and
deliberately, to within a few degrees),

and IF there is no deliberate or accidental conversion of the laser
beam's polarization between the laser and the sunglasses (e.g.,
deliberate conversion to circular polarization, effects of scattering,
birefringence in stressed windshield),

THEN only a small amount of the laser light will get through.

Rotate the laser about its axis by 45 degrees in either direction and
half the light will get through (which in terms of "dazzle" effects
means most of it gets through). Between 45 and 135 degree rotation in
either direction, more than half and up to 100% gets through.

The polarization direction of ordinary polarized sunglasses is set in a
certain direction because that's best for minimizing glare from
shallow-angle reflections. Any minimally competent bad guy could
therefore defeat their protection.

[And just for side interest, the LCD screen on my expensive 21" Sun
monitor is polarized exactly wrong, such that you simply can't use it
while wearing polarized sunglasses. The Sun engineers who designed it
knew computers, but not optics. Most laptop screens are polarized at 45
degrees; if you wear polarized sunglasses while using them you block
half the light, which your eye or brain adapts to and you don't even
notice it. Try tilting your head left and right while doing this some
time. I've observed that some of the credit card and signature screens
in California 7/11's also seem to be polarized exactly wrong for
polarized sunglasses.]