Traditionally 'date' has been a negative SEO thing in that Google prefers to surface "new" things rather than "older" things. As a result, web sites will pick o

Traditionally 'date' has been a negative SEO thing in that Google prefers to surface "new" things rather than "older" things. As a result, web sites will pick one of three strategies; Remove all date indicators from the content, Put the date on when "new" but remove the date after the content has been up for more than a set period of time, or use a js function to always render a date from yesterday as the date of the material. Google isn't about "reference" data (who clicks on ads when they are looking for a history of stories about topic X?) so the archival and reference function falls to meta services like Wikipedia where a human curates the history and provides links back to the that history. Of course such links get very few visitors and often the place hosting the content will simply retire it rather than spend a couple of nanocents on leaving it up, and the result is link rot. Yes, I am cynical about how Google is now an agent for "destroying the world's information" when at one point they were simply trying to organize it.