Looking at it from a company profitability point of view, I think overall arranger market share, r&d expense, and the time needed to recoup their expenses are factors. I am sure there are future innovations in the pipelines, but until one company comes out with one, the others sit tight and fix the bugs.
Personally I think the dying off of the
home organ/arranger kb players
and changes in technology music for the next generation
are a huge factor on what is to come in the future ..
it's only the natural progression. Hope I am wrong.