The discussion is not about making the term "advertising" so broad as to be useless. It's not "advertising" as in "any way that people notice a product or service". We're discussing "advertising" as in specific messages that third parties pay to have shown to people whose attention has been gotten by a second party.
In other words, the topic is the advertising where you give your attention to one party and that party participates (gets paid) to show you something else different from what you went there to see.
So, concretely: this is about paid ads on Facebook. This is NOT about products listed on Amazon that show up with compelling descriptions when you search for that type of product and clink on a link that wasn't higher in the list because someone paid for that.
When you go to Amazon and search, you are specifically choosing to put your attention toward products of a certain sort and asking for information. Amazon is delivering that information. There's marketing in how the products present themselves, but it's still something you are actively looking for, given to you second-party by the company from whom you are considering buying the thing.
When you go to Facebook to see how your friends are doing and your attention there gets sold to advertisers to show you unrelated products that may happen to fit your interests, that is the topic of discussion here.