The frequency isn't actually that high in the tech industry at large, just in the trendy areas everyone blogs about (and discusses on Hacker News). There are a

The frequency isn't actually that high in the tech industry at large, just in the trendy areas everyone blogs about (and discusses on Hacker News). There are a ton of people out there making a very happy, comfortable living maintaining Java/C# codebases. They learn about the new features in the latest language release and that's more or less it.