[ahje]

Problem is that there's a ton of shared hosting providers that won't support such a setup, as it would require a lot of modifications to 1-click-installers for WordPress. General WordPress users have no idea about such things, and the demand for more elegant solutions is therefore quite small.

That, and the fact that WordPress popularity stems from the fact that it's fairly easy to set-up without technical know-how, makes it unlikely that another path will be chosen in the close future.