This is basically the main issue, or that's how I see it. Artists within a genre follow a manual that makes them part of that genre and there are plenty of bands who don't do anything outside of that manual. That's either because they don't want to (mostly those that don't feel like stepping out of their comfort zone), they're being restricted by their label, or they simply don't have the musical qualities for it.
I personally don't mind if bands don't take that step. I agree with Bear however, that you're going to have to stand out, and you can't do that if you blindly follow a manual over and over again. That's what I deem "generic", in this case. It's a well-loathed term, but for me it equals bands that don't work outside a certain framework, yet a framework that is also used by a lot of other artists. That doesn't mean however that the experimentation that a band does outside of said framework will always be succesful. It can be a huge trainwreck and in that case you sometimes wish they had stayed INSIDE of the framework, lol. However, when a band plays outside of a certain framework and does it well, that's when I would say that yes, different does equal good, but only in that case. Sometimes the framework itself is enough too, but that depends on each individual's taste.