That's so obviously false. There are wikipedia pages about products, and they are not ads, either by definition or extension or induction or by anything. You don't know what "ad" means.
Maybe look up the actual definition of a word before talking about what it means by definition.
Was Wikipedia your first exposure to some product you previously didn’t know existed? Your “counterexample” makes no sense. Also, I’m pretty sure I make more money from advertising than you do, so I’ll stick with my understanding of what it is, thank you very much.
Before you look up something on wikipedia, you need to know that it exists in the first place.