>I have a hard time understanding how this can be considered an antitrust violation when switching is so easy.

Switching was never hard even in Microsoft's anti-trust case. You could easily download and install Netscape. Microsoft never forbid anyone from doing it and I can remember distinctly Netscape being included with my ISP's software floppy. What made the case was all about what was available default to the user. Interestingly under the same context you will find anti-trust violations if Chromebook became the majority and Firefox din't come installed by default.

It doesn't matter how hard switching is for the browser, what matters is how hard switching was for the OS - that's where Microsoft had a monopoly. In that, switching was very hard. They were trying to leverage that monopoly in a new market (browsers).

The key point. SW online does not have the charachteristics of natural monopoly. I have 8x choices in my integrated search bar (the default ones on Firefox). There are some network effects, or returns to scale from usage analytics that impact quality, but that is a different animal. MS Dos / Intel x86 technical architecture was actually exclusive.

Also, with MSFT was clearly a case of prediatory pricing funded by cross-subsidy from the monoply business. They set out to 'kill' netscape in its infacy as a business stratgy. Google is arguably just doing its job, and doing it better. Advertisers fell like there is "no choice" (because of scale), but they are sock-puppets. The consumer is the searcher. Advertisers have plenty of other places to advertsise online, so there is no monopoly.

"Yet I still wind up at Google around 20% of the time when I'm searching for terms with many matches"

I'm the same, and, unfortunately, even more often when searching for terms with very few matches. Google actually finds the relevant things.

Indeed, there are dozens of choices for web browsers, and even if you limit yourself to "mainstream" browsers there are still close to half-a-dozen. Likewise search, and there's nothing other than quality of results limiting any of them (i.e. using Chrome as a browser doesn't prevent you from using DDG or Bing for search, or even make it difficult).