This isn't at all clear, mostly because every "ad" professional I've talked to IRL is as allergic to real data as some people are to peanuts. What you've quoted is a sales pitch.
Where a giant group is compared to an extremely tiny group and the differences between them are used to make sweeping generalizations about everyone. When this is the quality to expect, it's just good practice to be skeptical.
Edit: Even if this weren't the case, the enormous spread of estimates when it comes to revenue impact really says it all.
You get "free" sites that you actually pay for indirectly through the ad costs embedded in the price of any advertised product you pay for.
Also, how is the claim that "Untargeted ads means less revenue" supported?
