Are you implying teaching isn't "real work"? That is kind of harsh.
I have used a 12.9" iPad Pro in my classroom for the last year and a half and have had great success with it. Using the combination of GoodNotes, and Apple TV, and LCD TVs makes it a great solution for presenting to class. Then with GoodNotes, it auto-updates the notebooks and posts them to Google Classroom for student access after class. I tried using the iPad exclusively, but found it lacking, especially when trying to create documents with equations (I am a math teacher). For that side of my job, the "administrative" side, it was less than great, and I use a laptop instead, but for my lessons, it has been fantastic. As you said though, it is questionable if that applies as "real work".