Aside from the fact that most used cars do not match your colorful description, I ask the reverse question: Why spend a huge amount of money on a new car that is going to depreciate like crazy the moment its wheels hit the street? Not to mention the loads of questionable technology they're carrying that will cost a fortune to repair a few years down the road. 

I let someone else pay the big bucks. Any halfway-decent new car costs more than I've spent on every vehicle I've ever owned put together over the last 50 years. Currently I am 10 years into ownership of car that I purchased for all of $1500.

The fact that they ARE used means they have lasted this long.  And have been tested.  I would never buy a new vehicle today.  Once you drive off the lot, the dealer treats you like you have the plague.  All the electronic junk they put on vehicles today is just more to go wrong and can't be fixed later.  If you're concerned about the "smell" get a $3 can of Ozium at the parts store (blue spray can).  That stuff will kill any odors from the 1920s on.

Its the worst time in history to be buying used cars

I wonder one thing: why some people buy new cars for a year or two and then get a new one. On the other hand this is a big plus for others. I paid only 75% of original price for a year and a half old car.

Every car I bought was used and pretty clean (except my first car) when I bought them. 3 of my cars were 5 years old when I purchased them. My current car that I bought in January this year is 2 years old and it’s basically the same as the brand new ones. I can afford to buy a brand new one cash right off the lot but I am cheap (not as cheap as Scotty who buys cars that are 10-15 years old) so why waste my money on a brand new 2021 Camry when a 2019 Camry is basically the same as a 2021 Camry ? Literally the only differences I noticed are the rims and the touch screen. Yea sure a brand new 2021 Camry will outlast my 2019... by like 2 years lmao and I don’t even plan to keep this car for more than 10 years anyway. 

because you're not filthy rich

Under normal circumstances I would say that a used car is more cost effective assuming you check it out thoroughly, are willing to do more maintenance, and don’t mind that things are going to need fixing more often. 
But right now (April 2021), I dunno. Used car values seem really distorted and in some cases I think buying new may actually be more cost effective.  You have to do the math on a case by case basis. 
PS: I have traditionally preferred new over used.  Because one advantage of buying new is that you know from the get-go how hard it is driven and how well it has been maintained. It not just about the “new car smell “.

You can get a perfectly functioning, new looking condition, maintained car as long as you shop around, buy smart, and all of this with a good 10 grand budget. New cars depreciate a lot and they are complicated and the quality isn't as good as they were a decade or two ago. I wouldn't buy a new car unless it has proven technology. 

If you were to come on the forum and ask if a "smelly, loud, old, beat-up used car with accidents and questioble ownership history" is a good buy, you already know the answer.

Most people buy used cars because they don't want to spend the kind of money on new cars and they don't want to pay for electronics as they age. The only time I buy a new car is when they use the same engine and transmission and a good amount of tech like the 2021 Tundras. 

IMHO, there are cases for buying new and cases for buying used.  Scotty provides his POV, and prefers used.

When I was on the market for a car, because I had no idea WTF I was doing.  

I still don't WTF I am doing, but have a little more confidence on what to look for buying used.