What is really needed is good package management on Windows and Windows developers not to be idiots. The former is happening but probably won't be released for a while and the latter won't change as long as Windows is the lowest common denominator.
However, I can't remember having any issues with uninstalled apps on Windows in a very long time. The last time I probably used an uninstaller was 10 years ago.
Not all developers are Microsoft Certified. It should read, "As long as anyone with a keyboard and a copy of C++ can sell software online, the latter won't change."
And I just fixed a computer with issues like this a few weeks ago. Some 'coders' need to be shot. Oh, two months ago I had a girl who deleted a program instead of uninstalling it; Registry Mechanic fixed most of the bs errors she caused.
Like I said, repair tool, not performance tweak tool. Yes you can gain performance in a few areas (namely Internet Explorer browsing), but for gaming, video editing, 3D Modeling, or anything hardcore? Not really anything worth bothering for.