My wife went to urgent care twice in three months because of a pain in her side. She was turned away with cough medicine. She finally went to the ER where a CT scan revealed massive tumors in her abdomen that had gone undetected for likely years. Genetic and semi-annual CA125 screening could yield quite a few false positives, but combined with her physical symptoms she may have had more cause to press at an incomplete conclusion and possibly could have had a different outcome. She underwent nearly $2M in medical procedures over the course of 26 months and died at 45 years old last year.
A few years prior to that I was spring cleaning one day and found a glucose test kit at the house. I had the whole family test their blood glucose. My youngest was 240mg/dL. We waited a day and tested again, same thing. We took her into the hospital and they actually admitted her for two days because they had no idea what to do with a child presenting with Type 1 diabetes that hadn't gone into full DKA. That's harmful, gross, and embarrassing. And this is a major children's hospital that was recently in the top ten in the nation for endocrinology.
In both of these situations, preventative screening could have or did have positive outcomes. I don't disagree with the effect that has been observed, but the conclusion being drawn from it is revolting to me. People should be permitted to make their own decisions about their level of knowledge of the state of their body. We only get one trip as far as we know, and I just find it unacceptable that people are willing to categorically deny diagnostic technology or bemoan its development because they they don't know how to support people trying to navigate the information it brings.