I work on Search Quality at Google. We have a firewall between Search Quality and Ads. We don't answer to Ads. Revenue is just not my team's problem. We come into work every day and look at our search results and try to get the most relevant answers ranked as #1, #2, etc. I never think about the impact of my ranking improvements on ads. I've been personally involved in dozens of changes, and I've never once heard anyone argue for or against releasing a change because of ads.
I can understand why someone might be mistrustful because of the apparent incentive to sandbag the algorithmic results. But Google has the long-term view: if we can keep satisfying our users' needs, the revenue will follow.
You can only speak about yourself, you do not know what goes behind the scenes. Firewall, like the investment banks have? Don't take personally, enjoy your paycheck and stock grants, you work for a corporation that answers to Wall Street. Listen to the earnings call once and analyze what the ad people say about "innovation."
But Google has the long-term view: if we can keep satisfying our users' needs, the revenue will follow.
Personally I no longer buy that. The revenue is now #1 and now Google is spending like crazy to keep the users. It started last year full speed