A 100k mile used car is already near the bottom of the depreciation curve, you probably sold it too cheap. Adjusting for inflation, $10k 10 years ago is $13k today. Covid did a number on the auto industry so all car prices skyrocketed, but they’re starting to recover: your hypothetical is only 15% higher when you adjust for inflation, which looks about right.

Cheap new cars don’t exist anymore because everyone want to buy fucking luxury SUVs or pickup trucks to drive their kids to school. It has nothing to do with EVs; we actually see this trend on the EV market too: GM abandoned their best-selling EV (Chevy Bolt) to instead focus on a bigger SUV (an electric Equinox, IIRC).