Key difference: the boomer kitchen is pretending to be something it isn't. Like the equivalent of an industrial hipster food court. It comes off as inauthentic and tacky (because it is)
I've been in genuinely rustic kitchens, even in the US, and they always have a sort of practical and timeless quality, even when the finishes are cheap or the cabinets are fiberboard, because the owner built them by hand tailored to their needs, instead of having Paco and Luis and Miguel slap together a crude mockery of Western perfection using home shopping network finishes
Even those simplistic millennial kitchens make sense in some contexts, and the upscale ones often do make use of subtle design motifs. I think you're retarded if you place them any higher than these Olive Garden tier suburban abominations.