I can see some merit to it, but you've missed the most important part, people don't buy expensive tier 1 products mainly for their features. They buy it for the reliability and support.
There have been lots of free alternatives to major storage platforms for a while, think of OpenFiler, Nexenta and certain VSAs. But I personally would not deploy them on our business critical infrastructure. While I could probably fix most problems after a while, but with business critical infrastructure you do not have that luxury of time. So if its deployed on commodity hardware that we built ourselves, which cavalry do you call when the chips are down?