I can't speak for the others but at least Android allows you to use any web browser you want (for example Firefox, Opera, Chrome). And it does give you a "browser selection screen" when you have multiple browsers installed AND open a link.
Windows never stopped anyone from installing an alternative browser either, or from picking a different default browser; the latter point is more of a usability point really (selection screen for every action or pre-set browser setting).
Microsoft got the fine and was required to put this thing up (as it did with WMP) because IE was installed by default (Opera cried it was unfair competition, as Real did for WMP; neither benefited significantly from their complaints iirc, while MS had to bleed for them) and, technically, because it was so integrated with the OS you couldn't uninstall it.
I honestly don't get why Microsoft / Windows is still the only party that has to do this, or why Microsoft himself hasn't struck back by having the EU put the same requirements on OSX and Linux. Then again, IE isn't available for OSX/Linux, so Microsoft wouldn't have anything to gain (unlike Opera / Real, that could compete with IE / WMP).
> I honestly don't get why Microsoft / Windows is still the only party that has to do this
because Microsoft has (had) a natural monopoly position on desktop OS and was found to abuse this monopoly to distort related markets (web browsers)
> why Microsoft himself hasn't struck back by having the EU put the same requirements on OSX and Linux
Because the requirement is applied on "dominant position" grounds. Neither OSX nor Linux have ever reached anything close to a dominant position, let alone abused it.
