I did say about 3 comments up that I could see them being a monopoly maybe in the Android ecosystem. I don't want anything to do with Android phones because I don't like Google, so I don't understand what is happening in that world.
Then IMO they would be a monopoly on iOS in a similar way. You change the default search engine on Android too, most people don’t know how/don’t care/etc.
Now I’m not sure that something you could actually define as a monopoly but they do control almost the entire search market on mobile because they directly control Android and pay Apple huge amounts of money to achieve the same on Safari.