They are doing exactly what they are paid to do: ask questions, try to understand what is happening, and crucially, if they subsequently find something wrong with their understanding, to admit so and investigate why.
This case seems to result from observation equipment and measurement techniques improving still further, revealing what may have been previously invisible, or hiding behind wider tolerances.
They are acting as real scientists are expected to do: constantly reviewing their work. If they had never done that we'd still believe combustible materials contain a mysterious substance called "Phlogiston", of negative density. We'd certainly not be able to talk about it like this - we'd not even have useable electricity!
