You put /s, but that to an extent is sort of true. Diseases can't be cured as effectively where remedies or mitigations are too expensive, but the same first world locations where medicine and care is most available also have a litany of factors working against health.
I don't believe though that this is inevitable, and I hope that the first world will continue to improve its situation, and that less well-equipped areas will somehow avoid making the mistakes and leapfrog these uncomfortable middle periods. We see this for instance with the Industrial Revolution, where those that can be credited with facilitating it generally did pretty poorly for themselves, but those who industrialised later were substantially better off.
