If I did this inquiry anywhere near where I work, I would see the same results you are seeing. But that’s in a city with a major university located right nearby, and a high concentration of jobs in the medical and high tech fields requiring 4-year degrees (or more).
If I did the same where I live, I wouldn’t see nearly as high of a rate of people with a degree at age 23. The public high school has a 67% graduation rate. And then not even half who graduate high school on time go on to college, and many of those students have to interrupt their education to work and save money. Many folks never even earn their GED. Some who do earn degrees don’t finish until their late 20s or into their 30s. It’s an old mill town, so much the same dynamic as @romanigypsyeyes described with the Ford plant. For generations families worked at the mills making good money. Then the mills moved to Mexico. But the mindset didn’t change, and the family finances got worse, so no money to pay for college for the generation that needs it now.