The numbers are “made up” and not based on any data. The data we do have is much more complex, murky, and even intentionally compromised to fit a narrative.

A more accurate way of phrasing it is that older generations have hoarded finite resources, locking younger generations out of milestones like buying homes, which also means locking them out of building equity and setting down community roots, which means a higher percentage of their money is spent on surviving instead of living, which makes them delay or abandon starting families, etc.

If you look at the studies, they will try to argue to generational “wealth” is akshually increasing against inflation and cost of living. But if you look more closely, you will also notice how they conveniently avoid the aforementioned facts. So while those fractions are not based on actual measurements, they still convey a very real concept that is being felt deeply and not being appropriately measured or dealt with.