randallsquared:

If this is true, why aren't they doing it?

Because the necessary information is difficult to obtain in a clear and convincing form, and it's drowned in a vast sea of nonsense that's produced on this subject by just about every source of information in the modern society. Therefore, a great many people are unaware of the problem, or even actively misled about it due to the prevailing hypocritical norms for discussing the subject.