Equally, when someone is considering buying a phone, they are unlikely to compare the lists of apps available for each platform when making their decision, just as car buyers don't look at the levels of tailpipe emissions when comparing possible cars. In such situations we accept that the government can intervene to prevent socially negative outcomes, even if it means increasing the costs (or decreasing the profit margins) for companies.

In any case, the problem isn't just the switching costs for users who discover their platform is limiting their app choices (or increasing their app charges), it's that companies trying to sell apps to users can't choose to simply "Don't use an iPhone", as Apple is preventing commerce between iPhone users and those companies, which is again not socially beneficial.