I don't normally get involved with this kind of discussion, but I believe Roland have recognized the bulk of arranger players are ex home organists - well, they have a range of home organs so why sell against themself? Also Roland are very good at quitting whilst they are ahead. They were very competetive with Hammond style keyboards in the VK7, untill Hammond released the XK3 (which was the best at the time) Roland and Korg quickly wound up R&D in that area...the buyers are too well educated and there are too few of them...just like arranger keyboard buyers.
I don't see Roland ever jumping in unless arrangers start to regain street cred among anyone under 62 years of age. Interestingly One of our retailers told us that a member of Staff at Roland recomended his particular customer buy an Audya as they are the best arranger currently available (his words not mine) which indicates to me there are no plans in the near future for totl arrangers from Roland.
Roland know what they are good at; Studio quality equipment for the production of recorded music, stage Piano's for live use and synth/workstations for home studios and occasional gigs.
Of course - I don't know this for certain...just a 'hunch'