I think there's really no way around the fact that web development is a mountain of legacy practices that few people can even logically justify. Learning the language is where you have to start, but even then, superset language fads come and go. You might pop open the hood on the source of a project and realize they never migrated away from CoffeeScript, or you might have to wrap your head around obsessively pedantic TypeScript signatures just to figure out what is going on.