You're right - it's not a problem for lawful gun owners. As long as they don't live in NY, and don't purchase any firearm after January 2014.
I'm sure you don't believe this, but there are those who purchase firearms for reasons other than nefarious ones. Competitive shooting is a big sport in some areas - there are even Olympic shooting events. Parts break on guns - guess you won't be able to replace the gun in NY.
The other problem with this is if this is implemented, NY is effectively driving some companies out of the state, and eliminating commerce as well by encouraging out-of-state companies to stop selling products there. In this economy, I'm not sure that's a wise decision. All for a technology that is "flawed and unreliable."
What is the point of rules that are not enforced?