You’re definitely not wrong but I believe the idea is that with a growing population and expanding housing availability and differences in desirability based on

You’re definitely not wrong but I believe the idea is that with a growing population and expanding housing availability and differences in desirability based on a number of factors, you get a gradient effect where older houses have more value than new houses, but there are new houses for people who can’t afford those older homes which have increased in value to a point where few can afford it