Ah, schoolboy error with the Corsa - you've taken the hit whilst the next person has potentially got a bit of value. But of course, you've only taken the hit of depreciation because you've got the car at the wrong time and got rid of it at the wrong time. Even getting one of those things right would have saved you a lot of money.
My first car was a Honda Civic that I bought from a doctor who was emigrating. My strategy was to get Autotrader as soon as it was on the shelves and get in there first for the right vehicle. The Honda was priced wrong so I was straight in. I was also given £600 off because it had a scrape on the side. I sold the car a few years later for what I paid for it after putting 50k on the clock. My mistake was selling it - that particular engine was known to go half a million miles. Honda make the best petrol engines in the world.
With regards to TCO, it's fine - as long as you know what the vehicle on its own costs. That's a fixed cost - you're paying it no matter what. Some of the other stuff are variable costs which are going to be subject to change. Know what you actually know - not try to know what you don't know and mix it in with what you know
Comparisons are fine - as long as they are real world decisions. Going to the extremes is disingenuous. You get lots of people comparing new vehicles with ones that are a few years old. Why? Because it makes sense for people who want to save money. That's always been my position. It's no secret that cars depreciate the fastest in their first few years. Sure, you'll always be able to pick a scenario or particular vehicle where you can play against that. But it's an exception to the rule. That's the mistake you made with the used/new car bubble recently.
I didn't buy the Corsa, or want it, I was effectively given it as part of the fleet, when I didn't manage the fleet. I pointed out how much a of a bad decision I thought it was (what was even worse was they bought two!), but was overruled, but later once proven correct I then ended up taking over running the fleet (as well as many other things). I said own, as it's part of the company I partially owned, but now half own, soon to be all of it. Effectively someone else was throwing my future money/ good work away, and I soon put a stop to that.
Buying a 2 year old car after such a hit might have been worth it for the guy who bought it off us, but I didn't want a new corsa, never mind an old one. I got a 5 Series, which was far nicer to drive, bigger, got ~20% off the new price and got 0%, so ended up a decent deal. Sure, worked out more TCO than a 2 year old corsa, but it was a far nicer car, which was important as I did a lot of miles, and it looked a bit better turning up to meetings in that, rather than a corsa. Things like that shouldn't matter, but they do. The point now though is, you can do that with an EV, but because the running costs are far, far cheaper, the better and nicer car which is brand new actually costs less than a worse car which is a few years older, it's great.
Honda do make good petrol engines, there's a reason they get used for most plant engines too.
Yeah fixed costs are fixed costs, which you define as that. Variable costs you can give parameters too, like ICE fuel will likely be £1.30-£1.80 with a 95% CI, that might get you 5-10 miles (or 13-35p per mile). Electric might be ~15-20p per kW 90% CI, that will get you ~4 miles (4-5p per mile). Sure electric might go to 30p again, but it's highly unlikely, but there are also times like now (and the last few months) where Octopus have paid me to charge my car up (or I can use solar). Don't think anyone's ever been paid to fill up their car with petrol, even when the oil producers were giving it away for free, and not many get petrol from the sky.
People wanting to save money and who buy a 4-10 year old ICE cars are not going to buy a new ICE car, the same as some EV driver who might buy a 4-10 year old leaf, they're not the market for a new EV, maybe not even one 1-2 years old. Compare cars of relatively the same age, if used, but if comparing new cars, then only compare with new cars, it's a different market. Sure, compare a new EV to a 3 year old ICE if you want, it's a different market, but if you're doing that, then you have to compare against a 3 year old EV too. This is where you're disingenuous, you don't even offer any like for like comparison, other than thinking all cars are the same. You may think that, but most dont.
Everyone knew there was a new and used car bubble (for ICE and EV), due to covid supply, it was always going to correct itself for that reason alone, and then even more when interest rates got jacked. Playing the market for how the market is, is the best thing anyone can do (if they understand their current position, then it's easier to understand future position). I've not made a mistake, I've driven 75k-100k cars for 2.5 years for 13-15k total outlay (better than forecast), not bad considering someone driving a 20 year old 20mpg car would spend that on fuel alone.
Anyway, bored of this now, again.