"Stronger revenue power" means that prices will rise, no? And higher prices are precisely the point of the antitrust laws. The Clayton Act prohibits mergers which would substantially lessen competition or tend to create a monopoly because of the "stronger revenue power" and the resulting higher prices for consumers.
Higher prices are not the point, monopolies are. And we are no where near a monoply with 4 strong players post merger. Read your last sentance, nothing about this merger meets that requirement.
This merger would not substantially lesson competition nor does it likely lead to a monopoly.