OK, while the criticism you've received is valid, let's look at a plus side:
Actually you're in a great position. You're young which means that all kinds of things are open to you if you start reasonably promptly on a good path, and you apparently have $10K you can put down. And you think you have the ability to further make monthly payments that would be substantial.
Let's stop and think what happens if you buy a genuinely good used car for the $10K.
Now, monthly payments are not due. You can save/invest the money.
After a few years, the amount of money you've saved combined with the retained value of the user car you've bought just now will easily allow you to buy an even better used car, AND have savings/investment left over. Quite a considerable amount left over.
A few more years down the road and if you want, you can be buying new cars this way. No payments: for cash, and with your savings/investment constantly growing. (Keep making the payments as if you'd gotten a car loan, but rather than a bank getting it as profit, you get it as capital.)
Look up how much money is just going into interest in car loans. The average young person over the course of their life will dump just an incredible amount of money into interest payments. Not only will you NOT be doing that, and thus be richer by six figures, but you will be EARNING compounded interest or dividends and capital gains. The amount that this can build up starting as early as you could be doing is pretty amazing.
The cost? Nothing but that of driving a $10K car for now instead of a $29K car, and for a few following years also a still-entirely-decent car instead of something you don't actually have the money for. But even if you are focused on cars not your overall finances, you could seen be driving better new cars this way than, instead, paying interest to the bank. That's lost money. Why go into that treadmill?
If a person has no or very little money to put down then they have to get into the interest treadmill. You don't.