Charles Stross has an excellent novel, "Glasshouse", a major plot point of which is that due to shoddy digital preservation practices, far-future historians know virtually nothing about ≈1950 through ≈2050 or so. What little they know is pieced together from fragmentary bits and pieces of evidence, with results that are at turns hilarious and horrifying when "put into practice" by historical re-enactors. Kind of reminded me of David Macauly's "Motel of the Mysteries" in some ways.