I have to disagree with you both and point out a different way to at least look at it.
Adoption of EVs could not have been the intent of the tax credit. Research and Development of EVs by necessity has to come before widespread adoption.
R&D is very high for the initial units, and once you're up and running the incremental costs are much lower. That directly fits with the # of vehicles limited per manufacturer. It means every manufacturer is given a fairly equal amount of assistance in R&D costs, rather than it all going to whichever single manufacturer got up and running first (and/or advertised best first) and then could have established itself as a monopoly with no competition. IMO, it's much more effective to subsidize the small numbers of initially produced vehicles than to have added a really small increase in price to the vast numbers of existing vehicles if the goal is to get EVs fielded and ready to compete in the market.
For a similar reason -- (just like is brought up with the Clarity) -- as these are the initial runs of vehicles, I don't think the low income people would be the best to subsidize these purchases. Aside from being viewed as a complete handout rather than a reduction in collected taxes... Do you really think low income are the best group to take on the additional risks? Higher repair costs, possibly higher insurance costs, etc, etc. Potentially longer repair times (as evidenced in these forums), more complicated and unusual features, the list goes on... IMO, incentivizing low income purchasers to take on these high risks is a terrible idea.
As there were no competitive EV options, increasing taxes or damage recovery fees on gasoline would NOT have really done anything to encourage EV development. It would have just made people spend more on vehicles and/or gravitate to more fuel efficient ICE vehicles.