I thought about it some more but it is hard to explain.

I wonder if your mental model is that a $20k discount applies at all future prices - so that when the car is sold for $5k that it's "actual" worth is $25k.

My mental model is that when the car is sold at $5k it is worth $5k and the $20k discount has disappeared (the value captured by the early owners).

Background: I'm a top 5% earner but I have friends who are struggling financially.

My opinion is that the discounts is money paid for by our taxpayers into overseas pockets, that benefits a few well off people. Strangely enough the discounts were introduced by our more socialist party, and removed by the incoming less socialist party. I don't believe the discounts are an equitable use of government funds.

I am also extremely sceptical that there is enough environmental benefits: the policy appears green but perhaps it is not (greenwashed).