If you're actually interested in flat earth theory you'll search for "Flat Earth." If you search for "Charting a Flight", You're probably not looking for flat earth content.

To me that has to do with search results being tuned for relevancy, not due the the perceived quality of the information.

Maybe, but you could also argue that bad information is irrelevant. If I search for "cancer treatment", it's not necessarily helpful for "black salve" to pop-up on my search results.

And a Flat Earth take on how to chart a flight path isn't relevant because...?