Being large is not illegal. Having a monopoly in a specific product is not illegal. The standard by which the antitrust officials judge companies is whether the company controls a sufficient part of the market such that the consumer is harmed. The problem with the current regulations with respect to Google/Facebook is that their products are "free" to the "consumer," and free can't be harmful (harm is higher prices). The state attorney generals complaint against Google tries to recast the "consumer" as advertisers. The reason Apple and Amazon get a pass is that within their "markets" they are still relatively small. For Apple, their market would be all cell phones (or in the Epic case the Apple lawyers define the market as all game platforms). Since they don't have a majority of these markets and consumers are free to switch within the market they can't be forced to change behavior. "iPhone" is not a market by antitrust definition. Amazon places itself in the total retail market where they are still less that 10%. As the law is currently written and interpreted most of what big tech does is not a violation of antitrust laws -- the laws do need to be changed for everyone.

> For Apple, their market would be all cell phones (or in the Epic case the Apple lawyers define the market as all game platforms). Since they don't have a majority of these markets and consumers are free to switch within the market they can't be forced to change behavior.

iOS has 60% of the US market[1], and Android 40%. The App Store has 100% more revenue than the Play Store[2], and the two are responsible for over 99% of all app sales. In the US, Apple has the majority of market share in the mobile operating systems market and the mobile app distribution market.

Both Apple and Google have a duopoly in mobile operating systems, and they leverage that duopoly to maintain their duopoly in the mobile app distribution market. To continue the chain, they then leverage that duopoly to dominate the mobile app payment market, as well.

Further, the colloquial definition of monopoly doesn't with regard to antitrust laws:

> Courts do not require a literal monopoly before applying rules for single firm conduct; that term is used as shorthand for a firm with significant and durable market power — that is, the long term ability to raise price or exclude competitors. That is how that term is used here: a "monopolist" is a firm with significant and durable market power.

[1] https://www.pcmag.com/news/ios-more-popular-in-japan-and-us-...

[2] https://www.businessofapps.com/data/app-revenues/

[3] https://www.ftc.gov/tips-advice/competition-guidance/guide-a...

To be more specific, the standard now is "whether the consumer is harmed" - which is notoriously hard to prove. It used to be "whether the competition is hampered" - which is much easier to prove, hence why anti-trust was much more aggressive back then. And why big biz gradually lobbied the new standard through.

That’s what Apple says, but isn’t it a bit early to conclude that Epic’s arguments (relevantly, that Apple is illegally monopolising the market for iOS app distribution) are doomed to fail?

> why can't a government agency just force [a specific business] to stop [doing a specific thing]?

(I am not a corporate lawyer) Hopefully didn't take editorial liberties with your quote, but wanted it to stand on its own.

My understanding is that the US, in contrast to many other advanced economies unofficially or officially, takes a dim legal view of singling out a company for any purpose.

Either a company is acting within the law, or they are breaking the law. What company doesn't (shouldn't) matter.

Which I think is wise as a standing order, as detailed specific-company intervention renders it more subject to politics, etc. Better to stick to the laws, and then allow the courts to apply them evenly.