The abundance of good used cars must be a Utah thing. It doesn't seem to be the case in the Southeast. Around here most vehicles over 10 years old are either in rough condition or overpriced. You actually have to go outside of Birmingham to find any kind of good deal on a used vehicle most of the time.
It also does require some level of willingness to fix things and deal with imperfections, which isn't what most people just looking for transportation want to do, and is completely understandable. After my 94 4 door Explorer was wrecked last September, all I could find locally was a high mileage 97 Explorer that was $1500 taxes and all from a dealer that just buys stuff at auction and turns it as quickly as possible, no clean up. It still had auction stickers. It had an engine I didn't really want, and needed work, but due to my familiarity with the platform and the fact nothing else I wanted was available, I bought it. I immediately bought tires, had the front suspension redone, and pretty much overhauled the cooling system. It has been a great truck for the last year and 14k miles, and I love it, but most people don't want to do all that just to drive a 24 year old Explorer with a crunched fender and almost 230k miles, even with an almost like new interior and everything working. Had someone just bought it and drove it without doing the work I did, it would have been in Pull-A-Part pretty quickly.
I kept looking since I still wanted a 91-94, and even went out of state to look at one that was kind of a letdown. I finally found one I wanted in July an hour and a half away for $2500, pretty much dropped what I was doing to go get it. I put tires on it immediately too and have done/still need to do other odds and ends. It's a great used car for me, but given it's a 26 year old 2 door vehicle with all the refinement of a Ranger from that era that gets 16 MPG, it's not really a good inexpensive family car. Oh and no airbags, though it is the first Explorer I've owned where the ABS still works.
I do see some regular cars and minivans in the 10-20 year range, but pretty much all of them have high miles, nasty interiors, foggy lights, fading paint, and need something. Things like Tahoes are either trashed, or over $10k.