This piece while interesting does not seem to differentiate mainstream articles vs highly specialized fields when it compares both in terms of accuracy.

I would bet it's not only profitability but also ROI that dictates how long a paper can part with a journalist for his investigation in a story before it becomes too much time in the eyes of management; the highly comprehensive piece does not bring that many more readers and possibly even less if the topic at hand is very specific.

As well politics on the other hand are dealt with on a daily basis and accuracy can more easily be measured even by the mainstream reader unlike a highly specialized field.