Well first of all what you linked supports my claim that 2/3 of Pharo users are MacOS and Linux users which I based on another survey which pretty much verifies what you linked.
Second the vast majorities of libraries out other for any programming language are cross platform so I am willing to bet that we will attract even more users if we emphasize cross platform support instead of libraries that OS exclusive. Of course that implies good support for Windows too.��
It will be kinda ironic Microsoft to beats us in the ability to be cross platform.