Was Joel Schumacher's loyalty to Akiva Goldsman the franchise's downfall come 1997?
If I have my facts straight, the original script for Batman Forever (written while Tim Burton was still possibly going to direct it and Michael Keaton still possibly going to star in it as Batman) was much more in line with the tone of the '89 film (it even ended with the Danny Elfman score soaring, the camera panning up the side of one of those expressionistic Gotham skyscrapers, the Bat signal glowing like a moon off the clouds, Batman silhouetted in front, cape billowing in the breeze, and Robin stepping up beside him).
It just needed a pass or two more by the writers to really tighten it up. Unfortunately, it was rewritten by Akiva Goldsman, who was Joel Schumacher's go-to writer at the time. And not in the right direction. Batman & Robin is really just Goldsman taking it even further than he did with Forever. To put things into perspective, Not only did the rewrite of BF hurt it, they also made him the sole writer of B&R (Batman Forever was mind you, also co-written by Lee and Janet Batchler), which is essentially why it stunk.