I suppose the original 1981 book will never be licensed, but I wish that could happen. The problems with the show were never with the book, and in fact, comparing the book (via the printer's proof that has leaked with Sondheim's corrections from a planned 1982 printing) with the current version, I think the original book is superior in almost every regard. I guess that Sondheim and Furth took the criticisms to heart and felt they had to start from the ground up--at least in terms of re-writing the book, but they should have realized the problems were entirely with the production itself--they threw the baby out with the bathwater. And it's not just losing the graduation framework. As Erick Neher said in his Hudson Review piece about the revival:
" I need to preface any analysis of Merrily We Roll Along with the declaration that I am in the sizable camp that believes that Sondheim and Furth’s revised version is maddeningly inferior to the original text. The major change is the elimination of the framing graduation scenes. Originally, the contemporary Frank, speaking to the young students, is forced by them to examine his past, delving ever deeper into the sources of his anomie. The title song, which recurs throughout the show as transitional music from year to (previous) year, is a deliberate provocation, a goad by the contemporary students to keep digging: “How did you get there from here?” they ask. “Which is the moment and where?” “How did you get to be you?” At the end of the original production, we finally arrive at young Frank’s high school graduation, and suddenly the moment is juxtaposed with the older Frank, still at his 25th anniversary, edified but devastated by the excavation of the past and forced to confront his younger, optimistic self. The layering of past and present is emotionally overwhelming and, not incidentally, central to the meaning of the show. All of this is eliminated in the revised version of the show. The title song is now not a motivating driver of the show’s backward trajectory, but rather a vaguely abstract expression of its theme by an unidentified chorus of random commentators. And the interstitial reprises have lost their pointed intensity and just feel like gauzy scene change music. The elimination of the framing device was not the only bad decision in the revised version. The role of Gussie, Frank’s second wife, was significantly expanded, turning a small, broadly portrayed character into a large, campy caricature. And in an attempt to make Frank more sympathetic, Sondheim provided him with a dreary song called “Growing Up,” which only makes the character seem more solipsistic than ever."
[. . .]
" The first scenes of Merrily have always been its most problematic, thanks to the backward chronology. Seeing disillusioned, jaded people at the beginning of a show is challenging: who are these unhappy characters, and why should we care about them? In the original version, the graduation scene depicts Frank at a moment of existential crisis, desperate to understand what went wrong. That feels relatable. In the revised version, we meet him at a party at his Los Angeles mansion, a moment of cynical, empty triumph, a parody of Faustian success. The original production cut these early, cynical scenes to the bone, in a hurry to get to the moments in the past where the characters were happy and connected. The revised version significantly expands what is now the first scene, the hideously awful party after the opening of Frank’s new film. The scene plays like a child’s vision of what mean, jaded grownups are like. Furth’s dialogue is so arch and Sondheim’s song “That Frank” so superficial, that the show is hard pressed to recover. In fact, it does not find its groove again until the second act."
(It always seemed curious to me that in the revised version, Furth and Sondheim have made the characters much more repellent--in the original, Mary is at least shown to try to act nice and sober at first, in the revision she comes on as an awful drunk. And while it's never good to push someone into a swimming pool, that always seemed more understandable than trying to blind someone by throwing iodine in their eyes...)
Here's the full review (it starts with a review of Here We Are, which I agree with as well.) https://hudsonreview.com/2024/02/the-ubiquity-of-sondheim/