Other than a couple of top-tier ad companies like Google and FB, ad companies tend to have really bad technology. They can’t attract the best engineering talent because everyone hates ads and they are a mess to work with. As a result, advertising code is garbage and runs like shit. News sites who are not primarily tech companies are at the mercy of ad companies to run their advertising and they end up piled down with third party crap. Most small ad companies are smash-and-grab efforts by a few ruthless entrepreneurs to vampire away small sites’ revenue or steal a bunch of user data and sell it. They all want to be acquired by a bigger company and walk away with some cash. No one is working on solving problems long term.