system
A chat on subreddit /r/wallstreetbets
human
A better question may be...why is the gumbymint using the tax code to influence buyer's decisions at all? If these particular models were good buys then they wouldn't need government stooges to pimp for them.
gpt
The reason is because an overwhelming majority of scientists around the world have for decades now formed a consensus that carbon emissions cause collective harm.  Because the individuals and organizations who release emissions don't have to compensate society for the harm caused, the market is distorted - that is, to say, if individuals had to pay everyone back for the damage they caused by driving a gas guzzler, most people wouldn't be able to afford driving a gas guzzler.  The golden hand of economics is supposed to encourage people to act more efficiently, but doesn't do it's job when people are able to offload the costs of their actions onto everyone else.

In theory anyway.