In NC there are child support guidelines which the courts use. They seem very reasonable. I have never seen arbitrary amounts ordered. And usually with joint custody, very little child support is required. I can’t speak for situations in other states, as I as not knowledgeable about that.
If NC had reasonable guidelines, there’s a good chance that I would have heard about it. Not saying for sure - but it would have been regarded as very big news. Most states, including NC followed recommendations and adopted guidelines presented by the collection industry — for the purpose described in the article. NC was not an exception - there were none.