Khan is fighting the best fight she can. The problem is she's woefully inexperienced in so many domains critical to the job.
I'm increasingly convinced her hire was a deceitful compromise to placate the base, because she says the right things, as well as corporate interests, because she can't follow through on them. I've seen two big law firms tell companies to pursue risky mergers; while there is a higher chance they'll be challenged, there is a much higher chance those challenges will fail.
Amazon, Meta and Alphabet are at the top of the list for lobbying spend
The US has two anti-trust authorities. FTC and DOJ antitrust division. US vs Google is DOJ case.