Ultimately its a balancing act between what we can know and what we can do about it. If you can’t treat a cancer (or your treatment is not effective, cf the radical mastectomy) then knowing who has it doesn’t help. As technology progresses and more cancers become readily treatable, it will make more sense to do early screening, and potentially full body MRIs.

But right now it is likely to cause a huge waste of time, resources, and yes, human lives to know about every little lump in your body.

Knowing every lump won’t save lives if you don’t act effectively on it. Focus on building tools and treatments that actually move the needle, not busywork that wastes time and resources.

Maybe, but there's a human element that can make things worse too. Take prostate cancer as an example. Most men die with prostate cancer. Most men don't die _from_ prostate cancer. It isn't usually aggressive enough to matter. Most people aren't zen enough to accept that though, so just knowing that you have cancer can add stress to your life with measurably bad health impacts from the resulting hormonal changes (reduced immune function, impaired sleep, increased clotting tendency, slower wound healing, etc).

You’re assuming a future with highly competent specialists who also don’t make medical decisions based on insurance requirements.

Unfortunately too many radiologists and specialists are more focused on upping cash flow than medical care.