The problem with ad-driven content is that the content is no longer 'pure' -- it is optimized to maximize eyeballs rather than serve its purpose (e.g. news is meant to keep readers up to date with current affairs they're interested in, art and literature is meant to, well, do what art and literature do). When these things are driven by the desire to maximize advertising revenue, they take on a completely different quality.
Was any content ever 'pure'? Newspapers always relied on ad revenue, and there was always the potential for a conflict of interest there. Whether it's internet sites or papers or TV news shows, they can't afford to annoy their advertisers too much.
The only ways to avoid this are either:
A: Go with publically/government funded content, which will likely have a government bias (or one that encourages people to pay for them).
B: Go with free fan/volunteer run sources which don't have monetary interests, and that's becoming rarer and rarer nowadays.
