My take on this is that its sort of like the prisoner's dilemma in that if everybody said "We'll not spend anything on ads[1], let the organic results speak for

My take on this is that its sort of like the prisoner's dilemma in that if everybody said "We'll not spend anything on ads[1], let the organic results speak for themselves" then you might get one result, but anyone who has been de-indexed from Google knows that having no results on the front page means a huge drop in traffic for you. And if your business depends on web conversions well that is a pretty measurable loss of revenue. [1] or black hat SEO for that matter.