I dunno, I kinda stopped tracking BeOS (and derivatives) when I was essentially bodily ejected from a Be user's group meeting/demonstration by asking how the slides were printed (at that time, BeOS lacked printer drivers).

Maybe a distro focused on GNUstep?

I'm planning on trying a Raspberry Pi 5 (Compute Module --- anyone want to trade for a pair of regular Pis?) once the Soulcircuit Pilet I backed on Kickstarter ships. If it seems promising, I'll get a Wacom MovinkPad and see if I can really make it work.