Unless I’m missing some information, Master has given Dobby a degree Dobby is free class of 2020 shirt just edited out of the next few movies for convenience. The plot of the fourth book was long and complicated and needed to be significantly edited to be adapted into a movie. Most of his role in the fourth book was centered around his relationship with Winky, who never appeared in the films. Neville being the one to tell Harry about Gillyweed helped streamline the plot and gave an extra clue to “Moody” being the one behind the plot to get Harry to the graveyard. I imagine it’s also much less expensive to have an actor appear in a brief scene than to CGI Dobby. She had sold the rights to her books to be made into filmS.