Counting things is boring and costs time and money which could be better spent on something less boring.
Having counted things – particularly having counted them for a long time – provides incalculable value in understanding what has been done and what might be done.
If you need a fifty year data series, you need collection to have started fifty years ago – starting now will do you no good at all (though it might cause your memory to be blessed half a century on).
It is of course easy to tell what we wish our predecessors of fifty (or ten, or five) years ago had done, rather less easy for them to know that then (or for us to know that for our successors now). That is in a way just a specialised version of a much more general problem of long term public investment, where there is a respectable argument that in undervaluing long term benefits, we end up with fewer long term assets being created than would be optimal – which applies as much, and perhaps more obviously, to investment in physical infrastructure
None of that is quite what this post is about – it’s based on a simple observation not only that some data which used to be collected is no longer collected, but that data on what data is no longer collected is itself not collected. Maybe that’s fine – nobody could seriously argue that data once having been collected must always be collected for ever more. But maybe the decisions on what to stop and what to continue have been driven more by short term expediency than long term value.