> that's dismissing Eric Schmidt's contribution
AdWords predates Eric Schmidt joining the Google board, let alone becoming CEO.
The rest of your argument is just silly reductionist wankery. Whatever the "core" of their business really is, they do have people working on those things. If you're going to make an incentives argument, make it; arguing where to put the "core" label provides as little insight as repeating "you're the product" ad nauseam.
The GP is exactly right. Yes, you do have incentives to maximize for advertising revenue. But if you want to maximize revenue over any length of time beyond the next quarter, you neglect things like having a product that's actually useful, usability, intrusiveness of ads, trust in your ability to keep information private from advertisers and the NSA, etc etc at your extreme peril. You can have all the advertisers in the world and it does you no good if everyone stops showing up to look at their ads.