Putting aside personal opinions of what a safe, modern or bloated operating system should be. It still remains to be seen that a large number of users use Windows 2000 and will continue to do so for the foreseeable future. As one of those people, I think I speak for everyone when I say that it would be greatly appreciated if Piriform were to continue to support the platform.
As I stated above, the command line version continues to work perfectly fine in Windows 2000; there is no deficit in functionality between Windows 2000 or Windows XP when it comes to the program actually performing it's job. Which means support was dropped for something trivial in the GUI version.
But without knowing more, that seams very lazy on Piriform's part. To be clear, Piriform has provided us with some wonderful and _free_ software, they owe me nothing in return. But as a long time advocate for their software, one does form expectations (however misplaced they might be). Hopefully one of the developer will reply with more information, so the matter can be put to rest.