> On average if I was charged 20$ a month for anonomised technical search services then I am fairly confident that they would be making more money than if I just ad-block everything like I currently do.

You should check out Gigablast (https://www.gigablast.com/). I came across their site yesterday, as one of a very few search engines who maintain their own index of the internet rather than relying on Google or Bing. It's delightfully antique, and surprisingly good for all but the most arcane searches.