The $25k car is going extinct?

Nobody else has said it so I guess I will.

The reason the US car industry does not want a $25k car is that the financing opportunities are crap for a car of this low cost.

In the same way that airlines exist to offer you a miles based credit card, the US car dealerships survive by offering you a loan for the car. Or perhaps, a car to go with your structured finance opportunity.

Buy the best used car you can afford for cash and forget all that dealership nonsense

The small and quasi-loophole to getting a good used car deal is buying a hail damage car. I genuinely don't understand why cars were made to have shiny paint. Cars drive on dirty roads with insects and pebbles abound. Paint doesn't matter. Car washes are crazy, except to abait rust

The issue you'll face is when you go to sell it – any noticeable hail damage means you are getting 1/2 the resale value if you can even find an interested buyer.

Ideally you should be driving the car until the wheels fall off anyways. Faffing about selling cars and buying newer ones is a waste of money.

Driving a car until the wheels fall off generally doesn't make financial sense. Keeping an old car on the road gets really expensive unless you have the space, time and skills to do all the work yourself. Then there is the opportunity cost of not having access to your car for days/weeks at a time while it is being repaired. Finally you have the stress of not being quite sure if your car will start when you turn the key or get you where you want to go.

From both an economic and quality of life point of view, you are better driving your car until it starts to get slightly unreliable and then quickly trade it in for a slightly newer used car. Buy a 5-10 year old car, drive it for 5-10 years, then trade it in for a 5-10 years old car is probably pretty close to an optimal strategy.

Does a Toyota Corolla ever get unreliable or uneconomic to repair?

Yes.

Prices are all jacked up vs what you get because a historical surplus of very well kept cars on the used market has lead to every idiot on the internet being told they're somehow magical.

A badge on the grill doesn't make 100k the of uber miles that the 3rd owner put on or being habitually driven low on some key fluid by the 4th owner any less destructive.

I ran a Corolla with a holed sump, and no measurable oil. I was going to scrap it.

After 3 months it was going ok so took it to a mechanic. They repaired it, said ‘don’t do that’ and it carried on for another 5 years before I sold it.