Long walk thoughts: I think I figured out my "dislike" of some scents as "synthetic".
Best analogy is cooking. An experienced chef or gourmet can tell roughly how much umami to expect from what combination of ingredients. A skilled chef can add just a touch of MSG to enhance this. In practice most home cooks already do so with stock cubes, and I read somewhere MPW quoted as saying most professional kitchens, including upscale, will use them liberally.
If it's just a touch, it will go under the radar as it's basically the same stuff that's naturally present in tomatoes, parmesan, etc. Add too much, and the umami is "off" compared to expectations, this is particularly obvious in some cheaper Chinese restaurants who use the stuff as liberally as salt. You can get used to it, but at the back of your mind an alarm bell is going off, as taste being different from expectations can be a sign that the food has turned for example, and this I think is what people feel when they are "allergic" to MSG.
Similarly, I expect a certain amount of projection from certain ingredients, and the complexity of natural ingredients (like rose essential oil with its hundreds of components) is part of a successful illusion of them being there. So, whilst a skilled perfumer can in theory replicate that illusion with just a few of these components balanced perfectly (this is, philosophically, Ellena's specialty; and I think Francis Kurkdjian is also very good at it), first, if they get it wrong the perfume will smell "off" or in the way that we associate with cleaning products (whose scents are simple for budgetary and stability reasons) and second, if they include components that are utterly new to the nose (such as Iso E Super) the alarm bells at the back of the mind start ringing.
I don't know if I want to get used to the styles that liberally use the likes of Iso E Super. It allows for exploring more perfumes than those limited by sticking to the natural components illusion code, just as Schoenberg and the Second Viennese School began a movement to move away from common practice harmony whilst deliberately ignoring the unpleasantness (subjective - to people used to Brahms - and objective - the closer to randomness, the more "noisy") of the results. However, you can ignore a Boulez concert by just not attending it, but the people around you cannot ignore your scent, and if they find it unpleasantly harsh or "off" they will be similarly put off as the scent beginner who has not learnt to appreciate synthetics yet.
So an analogy in classical music might be that your pre-1960s perfumes are the Brahms, Bach or - in the case of Jicky - Mozart dissonant string quartets of fragrance, whilst more recent approaches range from Debussy (Kurkdjian), Arvo Part (Ellena), and Bartok (Duchaufour), which are still at least somewhat related to CPH and rooted in the past, to Tristan Grisey (Molecule 01) or Brian Ferneyhough (Secretions Magnifiques).