Sure, but there is only one community that uses that vocabulary. No-one doing computational chemistry or machine learning or weather forecasting or quantitative finance (or any of a hundred other kinds of programming) calls themselves a "full stack engineer" or a "javascript ninja". Only guys assembling websites out of pre-built components (aka frameworks) like Ikea furniture, for companies to use for marketing.
He didn't even call himself a "javaScript ninja". He read a book that has that phrase in the title. Also, why do you assume building websites is mutually exclusive with doing something meaningful? Pretty bold assertion.
yes, because everyone building websites are mouth-breathing neanderthals who know nothing other than how to assemble marketing websites from pre-built web components and frameworks that do nothing important.