2030 or Twenty Thirty by Albert Brooks. Yes that Albert Brooks but the basis is that cancer is cured and how it affects the world. One way is that many more people live longer taking Social Security and the safety net out of reach for younger people. Society is differentiated as Olds and Youngs with great resentment amongst the latter. Medical care is rationed. It moves on from there but it's a story that makes you think and a fun read. Looked it up and it's about $5 on Amazon.