Having Market Share Dominance != Monopoly
Being a monopoly means having sole control over the supply of a market (conversely, Monopsony is demand). When people say Bing, Baidu, DDG, Yahoo, DDG, etc. are all a click a way, that means Google does not control the market supply.
Just because the majority of people choose to use something on an open market doesn't mean that thing has a monopoly.
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A. GOOGLE HAS MONOPOLY POWER IN RELEVANT MARKETS
A firm is a monopolist if it can profitably raise prices substantially above the competitive level. [M]onopoly power may be inferred from a firm's possesion of a dominant share of a relevant market that is protected by entry barriers. Google has monopoly power in one or more properly defined markets...Staff has identified three relevant antitrust markets...
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I think it's at least fair to say that some people with expertise in the space feel like Google could have monopoly control over one or more markets.
Also, a half-redacted document written by an anonymous person that was accidentally released almost a decade ago does not change the definition of a monopoly.
Yes, you can assume that it's written by someone who knows what they're talking about, just as much as you can also presume they were wrong because it was squashed. That's a moot argument.
None of that changes the fact that being popular does not make something a monopoly.
I didn't say that, though, or anything like that.
I did mention market share dominance. But that's often related to things like "A firm is a monopolist if it can profitably raise prices substantially above the competitive level.".
"may be inferred from a firm's possesion of a dominant share of a relevant market that is protected by entry barriers"
Arguably I left out "protected by entry barriers", but that seems obvious for search.
You're splitting hairs over the word popular now.
For example: https://www.documentcloud.org/documents/7273448-DOC.html (page 3)
I'm not saying they are "for sure" a monopoly. I am saying notable numbers of reasonable people with expertise in the space think they are. It's not as clear cut as you're saying.
This entirely new example you are giving is an example of partisan posturing, not evidence of a monopoly. Look at the political affiliation of every single person who signed the letter, and look how many days it was filed before the last federal election.
Again, being popular doesn't make something a monopoly, neither does being a popular target for Republicans.
Eric Shmidt: I would agree, sir, that we’re in that area....I'm not a lawyer, but my understanding of monopoly findings is this is a judicial process.
From: https://www.businessinsider.com/is-google-a-monopoly-were-in...
Also, the FTC's initial memo from 2012 that somebody higher up in the food chain quashed is pretty interesting: http://graphics.wsj.com/google-ftc-report/
In short, dominant market share in web search. Though I think you could argue other things, like dominance in affordable smart phones. Android is effectively a monopoly for people that can't afford an iPhone.