>>10721780So back in 1995, after Batman Forever came out and made a ton of money, the movie director and producers went looking for what villain to use next. Schumacher's nephew liked Mr. Freeze and he actually used to watch BTAS with him. It just so happened that around this time, Kelley Jones pitched his Mr. Freeze redesign that he had in mind(this was before the BTAS look became definitive). The movie guys saw this art, and thought it looked really cool, and that inspired them to go from casting Patrick Stewart to Schwarzenegger.
Kelley Jones jokingly apologizes for that in interviews
Incidentally, around this same time the Nightwing miniseries with the modern costume debut was being made, and what else does Batman and robin have? That Nightwing costume, in red and blue.