UNIX and Linux have been careful about avoiding simplistic designs. ZFS is a simple, obvious answer to a problem: just pack all the functionality into one big codeball and start hacking.

Wrong, wrong, and wrong. Why don't you read about something before you start shooting your mouth off? ZFS is layered. You can even, y'know, read the source before you start making ignorant claims. I guess this wouldn't be Slashdot if people did that, though.