If you'd let people mix and match elements from different eras of macOS, I'm sure you'd see some patterns regardless of when people got into Macs; similar to how people have lots of abstract opinions about architecture, but somehow the tourist buses always stop at the same cozy-looking old towns. Beauty and usability are not entirely subjective.
But more importantly, they existence of change is inherently important to the large-scale advancement of computing over time. Even if it is the case that a certain UI overhaul of a major operating system harmed productivity, the solution is not “permanently halt all software changes after this specific version that I have learned and enjoy using.” We ought to reject arguments that forced stasis is the solution any time changes introduce risk.