Contrariwise, just because my neighbor invests an assload of time in learning Blender's arcane interface doesn't mean that it was a good use of time and he wouldn't have been better served spending that time to learn his way around the actual functionality of a program with a saner, cleaner UI.
You're grasping at straws here. Prove it

The fact that people can use a tool for something doesn't make it necessarily a good tool. Political prisoners have written on cell walls with their own crap; they still would've been better off with a pen and paper.
Ahh come on, if don't have anything to say why even try.
This is like saying that if I haven't managed to break through a wall by banging my head against it, I just need to bang harder. Strictly speaking it might be true, but wouldn't it make more sense to use a sledgehammer?
And what kind of reasoning is that ? But hey that may be just what you need to do. Bang your head against the wall a few times and sit down in front of Blender and learn something new. In your case the sledghammer in Blender was there all the time you just didin't search long enough to find it.
I never bad-mouthed Inkscape, because I've never used Inkscape. But the fact that you can accomplish good results with the GIMP means only that its backend functionality is good, which I never disputed. It's still a giant pain in the ass to use.
Pain in the ass only matters in how often you do something. Of course I cannot know what you need to get done in GIMP from time to time basis but in my case after a few years using it quite often it's not hard at all. It takes me somethimes a a quick google to refresh my memory if I need to do something that I did a year ago and don't quite remember.
What. I was never talking about algorithms or backend functionality of any sort. What I said was that skinning GIMP to look like Photoshop won't make its UI behave like Photoshop. It'll still be a half-assed, incomplete clone of Photoshop's UI.
I can't argue because I'd never would want GIMP to look like Photoshop, in fact I run circles around Adobe products if I can. At work I have had to use InDesign or Illustrator. Often I eneded up doing it in Inkscape insted because that's the tool I used more and the UI i know better thus I worked faster with it.
My point is you can cry all day long about how good A is to learn instead of B, but at the end of the day what matters is how often you have use of the programs. Try to use Illustrator once a year and see how easy that is to use. That I call a pain in the ass.