We all have a different definition/reference of what's "analogue"
which is often driven by our ear sensitivity, where some people consider smoother/warmer more organic sound to be more "analogue" versus brigther/revealing/vivid to be more "digital". For example, if you are sensitive to 6k and 10k peaks (and can actually hear 10k well enough), you will find Fourte somewhat fatigue after extended listening, and probably need to step down to U18 or Trio. Some even found U18 treble to be a bit sparkly for their taste, and for those rolling back to Trio will be more suitable. Another thing, when I measure IEMs with Veritas coupler (budget-fi measurement setup), I get FR with higher peaks because it's a direct mic measurement of the IEM output. Professional measurements, like the one done by Jude and Tyll, use a model of a human head with a more anatomically correct earcanal structure. We all have a different ear anatomy and our earcanal is like a filter for the sound to travel through, which going to affect the sound and could explain the difference in our ear sensitivity, among other things. Bottom line, too many variables in a formula of how different people perceive the sound of one IEM