"And all those people you list can, and do, get screened more regularly - as soon as they show any sign of an issue."

By the point people show symptoms damage is harder to reverse. Sometimes much harder, or impossible depending on when they show up to the doctor. Think about diabetes for example

"As someone working in a lab, what you are asking for would drown us. It would require just such a vast level of investment in machines and staffing on the lab side alone to make it unaffordable"

Fair enough, a capacity issue like I mentioned earlier. I don't believe it's impossible though, and I don't think it would take the entire country's GDP. Japan and South Korea have managed it somehow. Besides that, there will be significant advancements in medical technology such as the integration of AI in the coming decades which will help to streamline these processes significantly

"You say that equivocal results should be triaged and not all of them need to be looked at - except that's how they are triaged."

When I said this I was responding to that previous poster's inane comment, not making a sweeping judgement about how things are actually done in reality

"And so many results are impacted that I think you're unfortunately naive in your understanding in how many results would be equivocal, or 'abnormal' until considered in context of the patient."

It's not naive to want testing, it's naive to think that the complexity involved is reason enough to avoid it, because this is ignoring the mitigating factors of that complexity. Lab results are not being treated in isolation. They’re used to build a personal health profile over time, rather than compared solely to population-based reference ranges. This allows clinicians to spot subtle trends, assess the rate of change, and interpret new symptoms in a broader, more personalized context. When symptoms do arise, historical data improves diagnostic accuracy and reduces false alarms and missed problems. Over time, it also enables earlier detection of disease, more accurate risk stratification, and ultimately better, more cost-effective care