It does, doesn't it! This is basically the reason scepticism in screening has risen (amongst scientists and medics, not the general population) - research seems to show that screening catches much more cancer but doesn't save many more people.

Rohin Francis does a good video on it, which you don't have to watch because it has references underneath you can click straight through to (the video is good though): https://youtu.be/yNzQ_sLGIuA

I am frustrated by this because it seems obvious to me that "more data == better" but I guess it makes sense if you think of the scans as having high amounts of noise, and us having a poor understanding of the system we're monitoring (this never happens in tech, of course :)).