Of course most European cities aren't operating a system on the scale of NYC's, since almost none of their cities are the same size. What's different is a series of almost night / day differences in quality of life, when using those systems.

The expectation here should be that we have stations as clean and functional as the ones in Stockholm or Copenhagen- i.e., working toward full accessibility, well-lit, floors not covered in decades of chewing gum, no puddles of urine or mysterious black gunk dripping from the ceiling, tolerable noise levels, no horrible odors almost everywhere, no poisonous diesel fumes from work trains, benches you don't dread sitting on, etc. Basically, conditions you'd expect in any normal public building (like a library).

I'm also aware that plenty of sub-par systems exist around Europe, and there's no point in lumping the whole continent together.