Blizzard immediately reached their zenith when they failed to understand what made people like their specific games. So in order to keep people interested, they did a superficial level of copying. Cargo cult mentality.It's not so much about "innovation", but chasing other people for ideas is not a good mindset to come from. Instead, understand WHO your fans are, WHY they are already there, and keep giving them the good stuff. Sometimes that includes cribbing ideas from others. But abandoning your original audience to chase after the newest shiny completely misses the point.
I think there's a difference between a feature checklist mentality and a core idea mentality.