The biggest disappointment was manufacturers moving away from the DIN standard. Companies like Pioneer and Alpine (even defunct companies like Eclipse) have had highly functional and usable touchscreen DVD/stereo/GPS units since at least ~2005. Things like GPS, bluetooth and voice control all seem to work without fail on the units I've had (my only issue has been a folder limit on USB drives). They also focus on sound quality, so you can get higher quality audio from the unit via RCA jacks to an amplifier. All of this for <$500 with GPS, <$200 without GPS. If the car companies want tight integrations (things like OBDII tying into display, climate controls) an OEM developed touchscreen makes sense, but as a consumer, using a 20 year old OEM touchscreen is painful. Modularity (the DIN standard) solved this, by allowing easy upgrades, but I guess that doesn't help move newer cars.
Infotainment systems are one of the biggest selling points if you've seen any car ad lately. Why let the customer upgrade the unit and keep that same car for a decade, when you can make that impossible and then entice them with the latest infotainment system so they buy a new car every few years.
Right, and that is what I don't get. The "fancy tech" isn't really that great relative to alternatives available in the past, but everyone is somehow unaware. Aftermarket stereos were mainstream during the 80's-90's during the tape->CD transition, so more people knew that they could upgrade, but in the mid-late 00's, hardly anyone seemed to know that you could swap a stereo out relatively easily. For modern cars I've looked at, the dash kit for swaps makes it insanely expensive. Popular vehicles may have custom aftermarkets, but niche cars are out of luck. So many people just look for any reason to get a new car, I guess that is just a side effect of treating cars like replaceable appliances?