Young people consume things that can be made at scale. The march of technology makes the things we buy cheaper, better, and more abundant. At the same time, it makes labor related to the production of that technology more valuable.

Old people consume 1:1 care. And as medical technology improves, elderly people survive increasingly complex conditions requiring increasingly labor-intensive management. At the same time, work with scalable impact is still getting more valuable, so 1:1 care positions have to pay more to win workers, so 1:1 care gets more expensive (cost disease).