XP was released in 2001. If they'd adopted Red Hat they'd have adopted 7, and upgraded 22 times, changing distro once to be on Fedora 20. If they'd adopted Ubuntu they'd have had to wait 3 years for the first release (confusingly numbered 4.10), and now they'd be on release 13. Even Red Hat Enterprise Linux didn't become available until 2002, and you'd be on version 2.1, unsupported since 2009.
If you suck at upgrading and want something that will be supported for 12+ years, Linux is not for you.