Resale value of EVs doesn't depend on mileage nowhere near as much as ICE cars. EVs are just much simpler machines and electric motors can do a million miles with no maintenance, and the only maintenance you have is the oil in the differential, which is often simpler because it is single-speed. Compare that to thousand different mechanical parts that all wear out in a ICE engine. Which is why ICE cars resale value is determined by the odometer.
What drives EV resale value is the health of the battery, which is influenced more by recharge cycles and straight up passage of time.
And the anecdotal evidence of a commercial fleet going bankrupt and not getting much for their EVs... Well yeah, would you buy from such a source? I wouldn't. They usually don't follow longevity advice for battery charging, because they have to optimize for time-in-use.
As an anecdote, I bought all my ICE cars second hand, and would usually sell them 3-4 years later just before major maintenance was needed. My EV is now 8 years old, runs like the day I got it and had 1 repair, when the motor that drives the window up and down broke and battery capacity is still the same, or if it changed it's such a small change I didn't notice. I don't expect to sell any time soon, if ever. I expect I will just do a battery swap in 5-10 years.