I keep hearing that, I just never see it. There are a lot of things nobody wants which corporations push in unison because they want them. And that's not even accounting for the meddling of the marketing department, which does matter.
[In my reply I'll be mostly specific to TVs. Cars is -at least for me- a more complex topic due to AI which I don't want to argue against because I am reluctantly positive about this development (I do realise the privacy issues). Its also a lot higher in price than a TV, which makes the risk/reward higher.]
1) The smart TV is a relatively new phenomenon (to me, I'm in my 30s and I grew up with CRT monitors, I suppose for someone who's 15 it doesn't feel this way). I don't own a TV, but when I bought a TV for my mother back in 2010 it was a dumb TV. Its still being in use, and it was made smart via a Chromecast (but it can be made dumb). My point is: the old supply hasn't dried up yet. Dumb TVs are still in use.
2) Part of the supply is met via the second hand market. If you don't see that, you are not trying hard enough. Go to eBay, type in a brand of a car made in 90s or 00s or fill in ThinkPad T61 or fill in a type of an old TV and off you go.
3) We're also seeing a conversion from TV being less relevant, due to streaming and Internet. This is akin to radio replaced by audio streaming, or PC replaced by tablets and smartphones. It may very well be that people use a dedicated TV less. In other words, I argue that there's less demand for TVs. (Which is why TVs are made more 'useful' by making them smart.)
4) The dumb TV is already here. It has a better refresh rate, and low ms than a traditional dumb TV. This dumb TV is called a 'monitor'. This is what I actually use as my current TV (I lied when I said I didn't have a TV, but its technically an 7+ year old monitor with a TV module. Its 24", and we barely use it).
So in short conclusion, concerning the dumb TV:
1 & 2) The replacement is relatively new and the customer has to learn the + and - of the newer version. The old supply hasn't dried up.
3) Demand has shifted. Customer perceives a smart TV as more capable.
4) Other product -still being actively made- satisfies demand.
I have no reason to doubt that supply & demand doesn't work in this specific market. Furthermore, you might want to take a look at importing from Asia. There's a relatively new market with a large supply of options over there.
Also see "not accounting for the meddling of the marketing department" - not all things just "happen". And while you make good points about streaming (having to schedule yourself around broadcasts is a huge drawback, after all) TV getting "smarter" and them being the way they are are still not exactly the same thing.
The consumer/customer can use any device with internet (PC, laptop, tablet, phone) to watch a TV series a few hours (?) right after or even during broadcast. Those devices can also be used to watch YouTube and all the other streaming platforms whereas a traditional TV can't. I wouldn't assume malice. I suppose the thought was "wait, what. More functionality than TV? We can compete with that."
Except that these onboard 'computers' on TV are weak, and profit margins are apparently too low to increase that. Which means you end up with something similar as the mess of Android. Devices with firmware too expensive to maintain.
Like I said, I use an old monitor as TV. My personal belief is TV as we know it is dying. We're going to see a merge of monitor and TV soon (with monitor capable being a TV) and the elder will be able to watch TV the traditional way. But youth generally don't. This means funding of public broadcast TV like BBC in UK and NPO in NL will get cut. Its a downward spiral, already set in process long ago in 90s.
Disclosure: I'm not from USA though.
