When you can get a 5-year-old used Honda Civic for around $9,000, an entry-level Model 3 is a lot of money. Also, an 8-year loan is 5 years more than the typical warranty. And you're paying a lot of interest. You're probably paying $400 to $500 a month on the 8-year loan for that Model 3, but only about $100 a month on the used Civic. Yes, there are people who can afford $100/month but not $400 a month. Also, the amount of fuel savings depends on how many miles you drive. The more miles you drive, the better an EV is. You'd need to drive a LOT of miles before the fuel cost for that Civic outweighs the cost difference between those two cars. My 2004 Prius burns even less gas than the Civic and would cost even less, used, today. (The same conversation came up when the Prius was new: a 5-year-old used Civic, burning twice as much fuel, would still have been cheaper over the life of the car, than the new Prius. The fuel savings do not pay for the car. A used car is always cheaper. People buy new cars for reasons other than "saving" money. People who need to spend less make do with used cars.)
I am a total EV booster and a Tesla fanboy. But a used Civic is still cheaper transportation than a new Model 3, and yes, there are people who do not have an extra $300 a month to spend on a car.
Given the advantages of electric, and the wide enthusiasm for Tesla, there are plenty of people who desperately want a Model 3, but who just cannot afford it, and plenty of others who will get one but will have to stretch their finances to manage it. I applaud them for making the commitment to a cleaner future, and although I'm as greedy as the next guy, and I will take every deduction the tax law allows, I have to admit in all honesty that it's more fair for that deduction to go to the person who has to struggle to buy a base Model 3, than for it to go to me who can afford $80,000 for the P-AWD supercar version.