@fatclue_98 OK your explanation makes sense. The reasons Microsoft has a monopoly in desktop are the same reasons there is a duopoly in mobile. Anyone who wants to run with the big dogs must provide something desired by the consumers. You like Windows mobile, I like(d) Windows mobile, but for whatever reason, the average consumer didn't. Therefore, the market shakes out with iOS and Android.
That said, my anecdotal observations caused me to conclude that the only people worried about the OS monopolies are the fans of whichever OS is not a participant. The WM fans are the ones complaining about the mobile situation. Likewise, Linux and Mac OS fans are not happy with the desktop situation. We all wish our preferences were on top, and we'll embrace any view that fits our agenda. Yet we're all affected exactly the same.
How about mid range Androids such as the OnePlus line? There is a plethora of those.