At first maybe. If they had the option there on the handset though, I bet many more would try it than currently install a third-party launcher. More importantly from the enthusiast's pov, if the overlay was switchable then it should be removable on a rooted device without breaking anything else. What's that old adage, "nature abhors a vacuum"? If there's a market for a Nexus-type device, and therefore money to be made, somebody will step in.