I was looking for a citation and instead found a number of vague or biased papers.

Suprisingly there’s an archived DoJ page that says that the same remedies may have been much cheaper to achieve through other means.

https://www.justice.gov/archives/atr/att-divestiture-was-it-...

YMMV. I don’t agree with the narrowness of this analysis, and would like to see some links to academic studies in economics and the study of innovation tbh.