People want lower power consumption AND power. Or efficiency, in other words. The argument about that was never in total isolation like you're making it sound. With Maxwell, Nvidia were able to provide better-than-Titan performance while drastically cutting power consumption at the same time. That's what the 'excitement' about that was. Maxwell was simply a more efficient architecture than what AMD had(has, technically).
If AMD can get on equal footing here with Polaris, then awesome. I dont think anybody will deny that is a good thing. However, if AMD cards use less power but are proportionally less powerful, then no, nobody is going to consider that a 'win' for AMD(though notebook and small form factor users will be happy to have even more options).
The cards need to be powerful in their own bracket. The R9-480 don't have to compete with the 1080Ti (or even the 1080). It should be a good upgrade to those running a 380/960 card. They get a lot more power with the same power consumption they had.