[its_ethan]

I think the issue is mostly from misaligned motivations from insurance companies and car manufacturers.

On the insurance side, they're motivated by finances. If the quote to fix a car is $10k and the car itself was only worth $8k, the insurance company is just going to give you $8k to find yourself an equivalent car to the one you "totaled". There's no intrinsic motivation for the insurance company to go for the $10k repair? Maybe allow them to have carbon credits or something for spending an extra $2k to keep the same car on the road? How do you tease out how much of a carbon win this is? (and who is in charge of deciding that?)

So then on the car manufacturer side, they're motivated by sales/ brand reliability. Maybe if cars were more repair-friendly that would help change the equation? That comes with the potential trade-off of new cars being more expensive and/or less reliable if they can't be as tightly integrated as they currently are. So if car manufacturers are motivated to make the most reliable/cheap car, they are going to forgo making them less repairable.

If you try and get both sides of this equation onto the same page, I don't know that you could trust that there wouldn't be some under the table shenanigans going on without making things so overregulated that both new cars and car repairs are both more expensive?

[sarchertech]

If you priced carbon emissions for building the car into the cost of new cars, it would fix this. In the case of your example, the used car would be worth more than $8k because new cars would be correspondingly more expensive.

Of course the problem is as you said how do you price carbon emissions.