Strongly strongly strongly agree if we want to write about sass Etc then write about that. CSS is an actual language with some vague relationship to a concept called standards.
Hey YOU, yes YOU the person who writes that cool CSS tutorial, but puts it in Sass, Babel, Haml, or whatever....please STOP doing that. Not everyone uses your fancy framework & it makes understanding your cool tutorial difficult. It’s distracting from what you’re trying to teach.