I read this article that Paul Galvin wrote in October 2017: Are Today’s SharePoint Developers in Jeopardy?
I helped Paul and other MVP’s (Tom Daly) organize this event as well as the New York SharePoint Saturdays.
Paul’s article is basically saying to Joe the SharePoint developer, “Get outside the MS TechNet sites and incorporate other non-MS technologies, like Node JS, Gulp, TypeScript and React”.
You still need domain knowledge in order to work with SharePoint.
Rest of the article on Linkedin