[wheelerwj]

Just like you have to fight feature creep in your products, you have to fight "shiny new tool / language / framework" creep in your skillset. Become an expert in your topic of choice and use the best tools to get it done quickly, whether its 20 years old or two. If you spend too much time learning new tech, you won't get it done quickly, but you shouldn't force an old tool to do something just because you don't want to learn something new.

As for the anxiety, turn off HN every so often and just focus on being a good engineer with your current tools. Nothing changes so fast that you can't go a few months or even a year without being in the know. When it comes time to stsrt a new project, spend a week researching the current tools and see how they fit into your stack.