GraySenshi :
they don't need to provide new updates. just keep the old download available. its not like its taking up server space or bandwidth to keep it available.
And it is a business decision to prompt people to move off old operating systems.
Same reason you can't buy a new XP (or Vista) license direct from MS.
$$$. Just like any other business.
And also...negative user experience:
"I downloaded the latest update for XP, and my PC still got hacked! Thanks, Microsoft!!"