There is a big discussion in this post about iatrogenics being introduced by these tests. It sounds like the fear here is that it'll tax an already burdened sys

There is a big discussion in this post about iatrogenics being introduced by these tests. It sounds like the fear here is that it'll tax an already burdened system with more patients (some of which just got a false positive). I'm failing to understand how that's any different from other blood tests: they signal a problem, then more has to be established to validate the signal. Nobody is saying "this test proves someone has cancer" and I'm pretty sure doctors already have to discuss how tests can be inaccurate with patients. I believe it's the case that symptoms of cancer (just like other illnesses) may be ignored exactly because there aren't any other signals to indicate cancer. Plus zebras and horses and all of that too. Perhaps someone does have symptoms but nobody connects the dots, and these tests might connect those dots. Is there some reason that this argument is invalid in medical science?