[Applejinx]

No, what would change is that you'd get people from hundreds of years ago expressing conservatism or liberalism _for the time_. It's neither fashion nor facial structure, it's more or less intensity of facial scrunch vs. innocence, or wariness vs invitation. This is going to hold true for all humans and indeed for similar enough animals so long as they have the ability for comparable postures and expressions (dogs and cats would have the capacity for posture but I think dogs are more capable of brow expression/mobility, and of course monkeys and apes are close parallels to human expression)

So you could, in a limited sense, tell whether you've got a hippie cat or one who wants the hippies to get off its litterbox :) the latter will give you more side-eye, and more of a narrowed gaze.