If it's not sensor artefacts, why have the readings not become clear over the last few decades, when the quality and quantity of sensors in use have improved by

If it's not sensor artefacts, why have the readings not become clear over the last few decades, when the quality and quantity of sensors in use have improved by orders of magnitude? Why is it still liminal? Has the visibility of these things gotten worse in lockstep with the improvement in sensors? Or (Occam's razor time) it was never real readings to begin with. And, I never assumed a single cause and neither should you, don't oversimplify. Every sensor has limits. There will be noise and artefact at those limits. You can't change that fact, with or without a f'n Jira.