Remind me again why Internet Explorer, itself, has anything to do with the Windows XP OS?
As we all know from our experience where Microsoft Marketing faked the courtroom proceedings, Internet Explorer has nothing, per se, to do with Windows XP. No browser, not Chrome, not Firefox, not Opera, not Safari, etc., is considered part of the operating system.
So, given that IE itself is simply an application, why wouldn't Microsoft patch a buggy application which is used by millions of its customers? The answer provided by Microsoft (that it's associated with the operating system) just doesn't hold water. As a professional in the software industry, I can symphathize with Microsoft's dilemma that Windows 7 & 8 don't offer enough value to entice half its users to switch, but, that's a different problem altogether than whether or not a browser application, which has nothing to do with the operating system, is to be patched.
Luckily, the advice stands to simply use Chrome or Firefox, and to dual boot Windows XP to Linux (typically Ubuntu), which, in and of itself, solves both problems immediately.