Yes a lot of people are okay with one company controlling 80% percent of a market if - they get there by relatively fair practices, there are clear and viable alternatives, and the consumer isn't forced to use them.
Now if the behavior of the "winner" starts to have clear, negative effects on consumers and consumers are no longer happy, the story changes considerably.
Maybe I could see an argument against the greater Google ecosystem (Android, Google Play, which does lock you into Google), or the distributor of content also being a content creator, etc.