Privacy glass + heat reduction?

[deutsch100]

Hey all! I have the rear climate control package, which includes the privacy glass in the rear. Does anyone know if that actually actively reduces the heat, or is it just light reduction?

I am going to get my front windshield tinted with a special film, that our local shop only uses for customers that want the windshield tinted, and he is telling me that even with the rear privacy glass, and the side window blinds (BMW Factory)...there is no heat reduction, and that I should tint the rear windows including the hatch/trunk area.

Thoughts, opinions? Danke!