I remember when I finally had two B3's that I really liked, one for the studio and one for the road I was set for life. Many keyboards later I had 3 / G1000's, and thought oh boy, I'm done buying keyboards LOL !!!
I think the bigger question is this the end of OMB's as we know them ? If there's a demand for more Arrangers they will be made but I don't see it. And as you said if you really dig into any of the better ones out there they are really all you need.
Bill in SC --- Roland BK9 (2) Roland PK5 Pedals, Roland FP90, Roland CM30s, JBL Eon Ones (2) , EV mics, Apple iPad (2) Behringer DJ mixer