Firefox's waning market share and need to suckle upon Google's teat to survive will only get worse and more dependent with time. So if Google doesn't meet all the qualifications of a monopoly now, it'll be much worse if the US waits to take action.
But they can literally already do that right now. Google just pays more. Nothing forces them to go with Google — they even switched to Yahoo for a bit.
This only ends with Mozilla getting less money since without Google bidding the value of the placement goes down.
If it becomes illegal to pay to set a search engine as default then they wouldn't be able to make those deals. Mozilla would lose all their money and the browser would die.
> If it becomes illegal to pay to set a search engine as default
Just as the Microsoft antitrust case was never about whether it was legal to bundle a browser with an OS, but whether Microsoft's particular act of doing so was illegally leveraging a monopoly in the desktop OS market into other markets, the Google case isn't about whether its legal to pay to set a search engine as a default but whether by doing so Google was illegally protecting an existing search monopoly.
You can't just ignore the relevance of the market power premise of antitrust cases to which it is central and pretend they are about the actions without regard to market power.
If you make it illegal for Google to pay for it but legal for others to pay for it, then you basically enforced that all search engine defaults will not be the most popular one since they will all pay for that position while Google can't. Then the status quo is much better.
