For example, if Apple is forcing developers to use their payments SDK to collect 30%, why can't a government agency just force them to stop?
Maybe there was a long official investigation by antitrust regulators, and that kicked off a long bureaucratic process that ends in a mandate restricting Apple from doing a very specific thing, maybe with an appeal/review process, expiration date, etc.
No need to get a bill passed that changes the law for everyone. A smaller company could still do that same thing, but it doesn't matter because due to their size, they're not immune to competitive forces. If anything, they'll have a harder time pulling it off because developers can get a better deal with Apple thanks to the new restriction.
Idk how the law works and whether the relevant regulators are able to do something like this. So maybe this comment is stupid, but it makes sense in my layman head at least.