You people are not getting me at all. The point is it has to be something that EVERY SINGLE LINUX DISTRO IMPLEMENTS THE SAME.
There's no way this will ever happen, since there's simply no way to prevent someone from implementing an incompatible install mechanism if he thinks the current one doesn't satisfy his needs, and no way to prevent other people from using it if they want to. You can't prevent Apple from selling OS X either, even though it's incompatible with Windows
when people use Linux they use Linux
This is what should change IMO. If two Linux distributions use different desktop environments and have significant differences in look and feel, software installation mechanisms and hardware support (since much of it depends on userland stuff), then from a non-technical user's perspective they may well be not just different "flavors" of Linux, but different operating systems
, and it could be more useful to market them as such. Just because two systems use the same kernel doesn't mean that they are at all similar from the end-users perspective.
You're never going to get a consistent experience by just using "Linux", but you may well have better luck with e.g. SuSE or Ubuntu.