Since the 'perfect capacitor' doesn't exist there are many complicated compromises made with formulations, the way the wire lead outs are connected to the plates, the ability to shrug off heat and so on so plenty of scope for 'golden ears' to think of all manner of wild theories based on,,,,,, 'whatever'.
Like the fact that you must use GREEN sleeved wire for ground connections. So while there will be small differences you are also in the realm of 'small differences now, this year but they will be different again next year (as will your ears). ALL of the old classic stuff (often with 'N' as part of the name has degraded over the decades so are not what they were when first made (and nor are we).