US FTC's statement about Google and antitrust investigation back in 2013.

We nonetheless recognize that some of Google’s algorithm and design changes resulted
in the demotion of websites that could, collectively, be considered threats to Google’s search
business… On the other hand, these changes to Google’s search algorithm could reasonably be
viewed as improving the overall quality of Google’s search results because the first search page
now presented the user with a greater diversity of websites.

Rather, we conclude that Google’s display of its own content could plausibly be viewed as an improvement
in the overall quality of Google’s search product

Yeah. FTC is going to do jack-crap about the situation given the tools that they currently have. The FTC is on purpose weak, the US Congress has sought to weaken it over the last three decades. People can go leave a comment on the FTC's website, but don't forget, US citizens, to stop by the House and the Senate. And if you need some background, here and here.

Now all that said, this isn't posted to discourage, it's posted to get you focused on what hinders the FTC.

Reporting it is a great idea.

I still need to get my head around what Google is doing and what the effects are, as previous experience says making reports to regulators tends to be more effective when I explain exactly what I'm complaining about. I once got the Solicitors Regulatory Authority (UK) to investigate a firm that was abusing process; after hundreds of complaints from hundreds of people, mine was the complaint they acted on (and I was the only person who got any updates on their investigation.) The right wording matters!

So once I'm sure I fully understand what I'm complaining about, off to the CMA I will go.

Done. Thanks for mentioning this.