Cancer is a very complex group of diseases, each one is a unique population of cells, and it's the sort of thing that just happens as you live
We could make cancer less common, but it's a really hard problem. People are resistant to behavioural changes like not drinking booze or wearing sunscreen all the time. A lot of screening is uncomfortable (people are working on it)
But we're making progress, look at the HPV vaccine

Sure we could be doing better if this weren't a capitalist hellscape, but that's not a conspiracy. That's just ubiquitous