Yup... Startac, I definitely see things the way you do. In my opinion, you've touched upon the elephant in the room in regards to Linux. I just recently decided to switch over to Linux for real... and it was because I just souped up my computer with all the latest and greatest equipment and lo and behold, Ubuntu was actually delivering acceptable performance when it had never before.
Computer hobbyists who design and who use Linux tend to be those who have top of the line desktop equipment and they want to have all the bells and whistles.
After using Ubuntu for a couple weeks straight I'm still seeing that there are problems with scaling up. For example, Nautilus does not like folders with hundreds of files in them, whereas with Microsoft operating systems scaling up has never been a problem.