Conversely... people can't see as well wearing these glasses or having treated windows so their headlights get brighter... this is kind of bananas

That's interesting. Mine don't darken at all, if very little. Instead they appear to shift the light, making a white-blue turn green, and turning yellow into orange - almost red. Doesn't help much with glare or light intensity, but the colour change means that those LEDs don't burn into my eyes causing me to see a black spot for a few minutes.

I've heard to keep away from normal " yellow tinted night driving sunglasses" or fishing/daytime polarized glasses, but I don't know the exact science.