I agree generally, but I was under the impression they had explicitly committed to ads over other revenue forms much earlier. Importantly, there was a point in Google's history where they weren't committed to this, and the internet would look a lot different had they not just determined ads would be sufficient for their business model.
Curiously, they had a solution of sorts in a program where you could basically bid for your own ad buys to remove ads from pages. For some reason they shuttered this program down. I didn't even know it existed until after it was gone, frustratingly. I thought it was a neat way to allow the industry bridge to other funding models.
(Or perhaps such a business model relies on tracking that's been deemed invasive. Who knows.)