Star Swirl is my forgetful artist. He’s, over the years he’s been alive, has let his studies control his life. Not out of anything other than pure passion of the craft. Constantly goaded to eat by those who care for him most, he only eats when it’s most optimal for work.
I also imagine him being much more Scrooge-like than his show counterpart. He’s more uptight and by-the-book than even Twilight in the early seasons. If it’s not in his nature to do it, he won’t.