JustSid: Your post reads very well and is absolutely true from the point of view of a programmer. Still I can tell you that there is a huge difference for people like me. I am creating a game level each week, importing around 80 models each week, around 100 textures each week. I worked with T3D, Gamestudio, Unity, UDK and C4 and there are huge and I mean very huge differences. In some tools I have to do a lot of steps manually, importing, material-creating, camera scripting and maybe even shader-editing.
In other tools I can copy everything into a project folder and it imports automatically, creates materials automatically (only one for each diffuse texture, so different models share automatically the same materials) and so on.

Then there comes the point where I need flickering lights and a camera movement through the level to create some nice preview for recording a video. This works fine in some tools just with an inbuilt animation editor. In other tools I had to script, to run, to see that it looks bad, to script again and so on. I would not have time any more to work on my assets.

I will not mention any names of engines here, just to not start any flames. But on my end I could save sooo much and I really mean very much time just while using the right tool for that.

Still I understand when somebody says he needs a certain feature or more performance and thus just has to live with worse tools, losing time there just to get a better performing game in the end.

But what I want to tell here is that there are advantages and disadvantages everywhere and the truth is just in the middle of what most people tell you.

Another very simple point of view is to count how many good games users of a certain tool produce per year. There must be a reason why one tool allows people to create games faster and easier than another.