"The only just monopoly is my monopoly"
I want to use Screen Studio, but it is a MacOS only app (and I'm on Windows). Is that Apple's fault?
Diversity is not an intrinsic good. It only is good inasmuch as it enables other things which are good. If the browser diversity we have (limited though it is) isn't actually providing choice to consumers, I don't see how it provides any value even if we do preserve it.
Once real Chromium is available on iPhones, there will be a monopoly.