PropPublica piece on how economic consultants are paid large sums to come up with economic analysis that favours mergers, and sometimes the predictions in these analysis are incorrect. Article gives a misleading impression, the government hires the same economists/consulting firms to do their own analysis. The economic analysis of one side is never decisive. They also seem to imply there's some impropriety involved in the billable rate for economists being higher than lawyers.
Most of the article seems to be an anonymous innuendo from the losing side of cases mixed with a questionable history of antitrust theory (they say the Chicago school of anti-trust is about efficiencies in scale, while it's really about the consumer standard). But the few examples they give of supposedly outrageous analysis by economists seem weak.
One example is about how economists argued that a Whirlpool+Maytag merger wouldn't lead to price increases because of competition with Samsung & LG. They use Traqline data ending at 2012 to claim that LG+Samsung were unable to gain marketshare. With weaselwords its hard to say the ProPublica analysis is wrong but by 2016 (when this article was written) Traqline shows that Samsung+LG both had higher marketshare than Whirlpool (I'm not sure if Kenmore is owned by Whirlpool though): https://asia.nikkei.com/Business/Electronics/Samsung-LG-lead-the-pack-in-US-home-appliance-market2
Similarly they think that the pieces designated villian Ozrag did a questionable analysis of the consumer harm of price fixing in ebooks by Apple. Ozrag's analysis claimed that Apple raised prices by 15% while the government's analysis said 19%, which seems like a very reasonable level of disagreement to me. Ozrag then made some claims that there were offsetting cross-subsidizations that improved consumer welfare which was thrown out by the judge. ProPublica makes that sound outrageous. But I assume a large number of arguments get rejected by judges.