Like someone else before me said, the install base is too fragmented to have any meaningful inroads made into the consumer desktop market.
You have different installer types, package types, desktop window environments, cryptic command line commands, etc, etc, etc.
Yes I realize these things represent choice, which can be overwhelming for "the average user".
I tried a few different distros for home use and the best I found were Fedora and Ubuntu, but even they have their shortcomings.
Ubuntu is probably the closest thing to a unified consumer distribution I have seen.
I honestly base a consumer distro on how easy it is to set up printing.
Long story short, got tired of fighting with everything or finding some obscure forum post on how to enable something for fix something and switched to a Mac.