1) Automatix. For some reason, people think it is somehow built-in to Ubuntu. It's not. And it's not idiot proof.
2) Using "sudo" by default. This is just plain ignorance. The arguments for and against it belong in the "recurring discussions" sub-forum, so I'll leave at it this: many power users on other distros disable the root account and use sudo.
The optional third part is the inclusion of the restricted modules in the installation CD. To me, that's more a matter of convenience than idiot-proofing.
Long-story short: I haven't seen a single good argument so far for the contention that Ubuntu sacrifices functionality for the sake of coddling the newcomers.