There isn't anything this does that the ErgoDox-EZ doesn't do, besides the adjustable thumb cluster and apparent build quality.
I wouldn't call this a next-generation ergonomic keyboard unless it also had integrated pointing device options like the UHK has.
The thumb clusters need to be bigger and closer to the alphas so they're more powerful and more easily reached.
My board: https://flic.kr/p/LJdbeC
I started out with an Atreus42 in 2016 and really loved it, so I totally get that outer columns are superfluous in most circumstances. The same could be said about most extra features on this ZSA Moonlander board overall, although I think there's some utility in being able to leverage the non-essential keys when it's convenient, especially when it costs that much. Say for example one wants to use it for gaming - most games expect there to be an outer column.
(Shameless plug) Here's my keymap. It doesn't require outer columns, and needs just 34 keys: https://github.com/1MachineElf/qmk_firmware/tree/sb4dv/planc...
I like the visuals of the ErgoDox-EZ the most, but still willing to wait for the new keyboard.io, whenever that one comes out.
For me, at least, it's not a big win. I'm mostly touching the inner edge of the key because my pinkies aren't that laterally flexible.
I like a lot of tilt and low to the desk, and that extra 0.5u of width ends up raising the whole thing more than it needs to.
I have large hands and the ErgoDox thumb cluster is just too damn far away. Bringing it within reach is a meaningful improvement.