Different taxes are applied for different reasons. The luxury tax is applied in the belief that those who have a higher financial status should be contributing more to the public funds. The pollution tax is applied in the belief that those who pollute more should also pay more and to potentially discourage people from buying polluting cards( in the presence of a better alternative, but for most people the model 3 might as well not exist right now because it's too expensive).

The truth is that there just aren't enough people who can afford a model 3 to make a dent in global warming. The model 3's effect is in terms of dealing with the risks involved with mass production without investing the amount of money needed for a truly disruptive model( think 15-25k cost, that would take A LOT more orders).