If you’re talking about unstructured data then I can understand your metaphors to some degree, though a lot of the data comes in structured form. Lot of the data (addresses, geolocation) are still alive to be considered as part of a museum.
Even if a dataset might not be fit for purpose, it can still be used for further investigation or other purposes. Some datasets can be compared against other datasets.
You don’t always need to prepare the data by yourself but find incentives for other people to help.
“To call in the statistician after the experiment is done may be no more than asking him to perform a postmortem examination: he may be able to say what the experiment died of.” Ronald A Fisher, cca 1938)