Laugh or cry, you choose.
In places where it is very hot the entire day it is common to purchase some type of shade, often made of thick cardboard, that you place on the inside of the windshield to block the heat. There is a little cutout in the shade so you place it around the rear view mirror.
The fact the manufacturers have to place, in writing on the shade, the car is not to be driven with the shade in place is an indicator of our current times.
= new reply since forum marked as read
I'm wondering if it isn't a "thing" for corporate lawyers to ensure job preservation!
Tons of sites about the same - here's one:
https://www.rd.com/list/funny-warning-labels/
would even be bothered to read the directions for use; the corporate reduction of liability by singing to the choir of unfailing readers of package inserts and directions that just want their freedom/right to chose their behavior for best practice/use and do it, just this once!
Oops - just what is "obstruction of vision" - evidently and anecdotally, only a very common human user error!
Agreed -
and noticed the warnings when looking for the dosage info.
The first warning: Do not give to children to make them sleepy.
Not as bad as the sunshade but still a 
Just stick your head out the driver's front side window and watch the road and on coming traffic from there.
If you leave the sun shade in place on the windshield it will block the sun's rays from entering the passengers compartment and causing excessive heat to the interior of the car. That way your air conditioning costs will be much cheaper to cool the car.
