Does antitrust law practically exist anymore? It doesn't seem like the political will exists for it the way it did back in the 90's with Microsoft.
1) Mergers are often denied in the US, but once a company is large enough, there's no breakup.
The Bell breakup didn't really help, as some of the Baby Bells later merged into AT&T, though alernate equipment mfgs. and long-distance providers emerged.
2) The US govt. is reluctant to assess serious penalities against large companies because of the layoffs at Arthur Andersen in 2002 due to the Enron scandal.
Also, the SEC will only initiate cases where the trial is affordable and predictable, partly because of the Countrywide scandal where the founder had comparable resources to the US govt., and ended up settling. The case went on from 2008 to 2016.
(The SEC has actually sent letters to large companies asking them to not pay legal fees for executives - pretty desperate.)
https://abcnews.go.com/Business/Decade/arthur-andersen-busin...
https://www.investopedia.com/terms/b/babybells.asp
3) As banks become bigger, they become "too big to fail." Wells Fargo should have been shutdown after admitting millions of counts of fraud against account holders in a systemic effort to increase fees to move their stock price.
Breakups work when they separate a vertically integrated monopoly. You separate Unix from AT&T and it thrives. Netflix is better than Cable TV specifically because it isn't the cable company, and separating TV service from the last mile provider would be useful. In general, prohibiting a monopolist from operating in any vertical markets is useful, because it prevents the monopoly from being extended into the other markets.
The baby bells were separated horizontally -- and they each still had a regional phone monopoly. That doesn't work.
I don't disagree that the government has stepped back in many ways, but part of the problem (such as it is) is that the enforcement people ostensibly want would require far more dynamism from regulators, which is not something the American system is tuned for, especially at the federal level. Moreover, given the current political factionalism, we're increasingly less likely to see the necessary legislative dynamism. And finally, there's a creeping judicial activism that is beginning to upturn decades of administrative agency law, throwing a wrench into everything but on balance reducing agency flexibility even more. Just look at what happened to the Consumer Financial Protection Bureau.
I think the only practical way forward is to rely on individual states, permitting states like New York and California to extend their roles. But that, too, would require some acquiescence from all three branches of the Federal government to even approach the kinds of changes people seem to expect to see. Contemporary politics similarly disfavors that approach; in some ways even more vehemently--conservatives know that they would lose their obstructive powers, while liberals tend to only accept federal-level policies as legitimate and efficacious. For example, take the Federal Arbitration Act--conservatives would fight repeal tooth & nail, while liberals can't even contemplate the thought, preoccupied as they are with enacting positive regulations federally.
Kind of, the baby bells running Cingular bought AT&T and rebranded