I’m not even sure thinness was something consumers ever would have demanded

I am entirely convinced that most "features" on modern devices are not "something consumers would have demanded". Sure, different lenses is nice if you're a hobbyist photographer, but do most people really need more than a single back-facing camera? Do most people want to have wireless earbuds at the cost of not having a headphone jack? Do most people want glass backs and other such gimmicks that make their device more fragile? I've been told for decades that the modern economic system is great because competition forces manufacturers to prioritize what is best for the consumers. But in the context of smartphones, it feels like the roles are completely reversed. Manufacturers come up with some bullshit and then mount psy-ops (ad campaigns, online astroturfing) to convince the population that it's worth their money