I would argue it is premium, not luxury.
Premium like a flagship Samsung, offering extra features and quality for the buyer, usually for a disproportionately higher price. Luxury is where there is no extra value offered beyond brand recognition, signaling to yourself and the world that your can afford it (like the obscure clothing brands you mention).
Not many luxury phone brands exist, maybe Vertu with gold and diamond set phones. Cars are an easier comparison, premium is e.g. MB, Audi or BMW, while luxury is Bentley, RR or Ferrari.
Rolex is also more of a premium product within the watch market, it is machine made and mass produced to a very high quality level, offering additional value (like better accuracy, less steel corrosion, longer service intervals) compared to other automatic Swiss watches. On the other hand, luxury hand made watches like Patek Philippe or FP Journe are not competing with others by offering better technical parameters, but dominate due to their brand recognition, making rich people beg salespeople to get a chance to buy them.
This of course doesn’t really make a difference beyond marketing, as most people cannot afford a 10k Rolex or a 200k FP Journe either - but they do hold a very different position in their market.
To answer your question, I think most humans are very social, and always seek to stand out with status and personal brand within their group. Capitalism offers the easy way to do this - buy this thing, and show the world what you are worth. It unfortunately works, as it targets our strong primal instincts.
I think this chart overcomplicates it a bit. Almost a decade ago, I worked on a very short project that touched on this topic. One expert explained to me that the difference between level 4 and 5 is that you don’t need a steering wheel or pedals anymore. L5 can drive anywhere, anytime in all situations.