We've gone through die size, clock speed, instructions and operations, the transistors count. All are stand-ins for "complexity" which is why some people question if the law ever existed.

That said, regardless of the "real" law, until recently the colloquial usage has always been a stand in for how "quick" a processor is. In that sense, you really need to do some hand waving around core counts and even then it doesn't really work.

Maybe more importantly, one of the most important processor markets are mobile and servers which are largely focused on less complex more efficient processors like arm.

So outside of marketing, it's very easy to see why a lot of people think Moore's law is dead and we're all better for it. We can continually make better processors without trying to meet some arbitrary metric that didn't really mean anything useful to start with.

E: aggressively agreeing