By the way, this is the story of every regulated industry as it starts to fall under the specter of regulation. Everyone says "Who are you to tell me what I can do? Where will it end?" The answer is that laws will stop changing when public opinion stops changing.
I'm sure that those getting rich at the teat of Carnegie, Rockefeller, et al were none too pleased about increasing antitrust regulation in their era. It went against everything they had built their empires upon. That's too bad. It had to be done to address an urgent threat to American way of life. Gun control advocates see mass shootings in the news and see such a threat.