Which of those got Google to where they are? Apple?
This feels like a bait question because the answers are so obvious.
How is Chrome a monopoly? Google made a good browser and customers chose it over other alternatives. Now you can argue that chrome isn't a god browser. But that's your opinion. People are voting with their feet. Does google have an obligation to make their browser suck?
The bigger issue is that website owners have become increasingly hostile to crawling, and that's effectively closed the door behind Google, because that's when it starts getting more legally contentious. Which is why I think they should be forced to open up their crawl to everyone, so that we can have meaningful competition in the indexing/search space.