Why not XP? The have no interest in supporting it. And millions of people still want to use it.
Because this would allow these millions of people to continue using this fork of XP rather than eventually buying a MS operating system.
But this is the attitude Microsoft needs to eliminate. The days of making money on operating systems is rapidly fading away. They already gave away Windows 8.1 as a free upgrade, so they're aware of it.
An open source XP would get many hackers interested in Windows, something they desperately need.
Citation needed.
They are definitely making money on closed-source operating systems and operating system tools:
http://www.microsoft.com/investor/EarningsAndFinancials/Earn...
> They already gave away Windows 8.1 as a free upgrade
It wasn't free--it took a couple of hours of my time!
Is there still any value for Microsoft in Win9x?