Deep Purple, jQuery and the role of legacy

There are people, groups, works and topics that are old just in terms of age, and everyone and their dog wants to replace them for good, often for their age alone. But that turns out to be a wild goose chase, since these are so good at what they do, and/or they command so much mindshare, that they keep going for decades. See Emacs, Vim, COBOL, paperbacks, notebooks, email.