As far as I know, it is actually the focus on "consumer harm" that is, well was, the new thing, introduced in the 1980s under Reagan, and it largely gutted antitrust law. And that was exactly the purpose.
For much of that history, including the seminal breakup of John D. Rockefeller’s Standard Oil in 1911, the ruling antitrust theory was “harmful dominance.” That’s the idea that companies that dominate an industry are potentially dangerous merely because they are dominant. With dominance comes the ability to impose corporate will on workers, suppliers, other industries, people who live near factories, even politicians and regulators.
The election of Ronald Reagan in 1980 saw the rise of a new antitrust theory, based on “consumer welfare.” Consumer welfare advocates argue that monopolies can be efficient, able to deliver better products at lower prices to consumers, and therefore the government does us all a disservice when it indiscriminately takes on monopolies.
https://wolfstreet.com/2021/08/14/antitrust-bombshells-in-th...