Minimal changes have occurred to the concept of “antitrust” since its inception as a form of societal justice against corporations, at least per my understanding.

I doubt policymakers in the early 1900s could have predicted the impact of technology and globalization on the corporate landscape, especially vis a vis “vertical integration”.

Personally, I think vertical integration is a pretty big blind spot in laws and policies that are meant to ensure that consumers are not negatively impacted by anticompetitive corporate practices. Sure, “competition” may exist, but the market activity often shifts meaningfully in a direction that is harmful consumers once the biggest players swallow another piece of the supply chain (or product concept), and not just their competitors.

There was a change in the enforcement of antitrust law in the 1970s. Consumer welfare, which came to mean lower prices, is the standard. Effectively normal competition is fine and takes egregious behavior to be violation. It even assumes that big companies are more efficient which makes up for lack of competition.

The other change is reluctance to break up companies. AT&T break up was big deal. Microsoft survived being broken up in its antitrust trial. Tech companies can only be broken up vertically, but maybe the forced competition would be enough.