Perhaps quality of recent scientific research volume has not increased as much as quantity, so the importance of each individual research piece is lower. Also,

Perhaps quality of recent scientific research volume has not increased as much as quantity, so the importance of each individual research piece is lower. Also, selection bias at work: like hit music, only the good stuff still gets played, and if there is sea of lower quality new work, the old foundational classics will be favoured now that they are more easily found. This helps with a dilemma I often face - that of buying recent or older works on Amazon or elsewhere. Instead of always buying the most recent publications on a topic, why not buy the axiomatic decades old works.... indeed in my collection I often find these display more information density, and higher clarity of thought: the latter being inversely proportional to ease with which a document can be produced.