I play a Wersi Abacus Duo Pro OAS 7 that has both a 61 note keyboard, 76 note keyboard, and 25 note pedalboard. Even if Yamaha did offer a new 76 note arranger it couldn't compete with the sound quality or the functionality of the Wersi so there's really no point in me going backwards.
There are other manufacturers besides Yamaha that make cutting edge products but cutting edge technology can cost a lot. Yamaha has a large market share due to their lower priced arrangers which sell well to home players, hobbyists, semi pro's, and the occasional pro, but that doesn't mean they have the best product available. Where Yamaha markets to the masses Wersi markets to those that want what no other arranger has to offer. That may come at a premium but for those that want what no other arranger can do, there are but a few choices to be had.