Although tech may not "differentiate" one car over the other, is not the same as sayng that because of that, tech is useless. Onl gimmicks for gimmicks' sake is useless. Here, "tech" includes modern computer design, independent suspension, traction control, and modern metallurgy. Just because it doesn't seem that much "different" to you who equate "tech" with computers and think they're all the same, so nothing to differentiate them from others, doesn't mean we should then go back to the design and tech of the 1940s (or 60s) or wherever else you want to stop.
If you think the tech is in cars in order to differentiate themselves, I don't know what to say.
I don't buy something "techy" to differentiate myself. The tech I buy serves a purpose, such as my bike (biycle) GPS, laptop, phone, and especially my prosthetic leg which is made from carbon fibre and titanium (yes, really). The shape of it was done by scanning my leg stump. How about that. Quite cool, I think.
In short: I don't use that tech to differentiate myself, I use it because it has a purpose. I would also like to reiterate that "tech" is much more than CPUs and computing power.