Not enough keys
The difficulty with a minimalist keyboard is no 10 minimalists will ever agree on which keys they need. This is only an issue when a hardware manufacturers want to avoid bankruptcy by selling the stock of the last run they made.
While some of the splits would be worth a serious look to me if I was logging more mileage, most of us need something that is close enough to one of a small number of "standardish" layouts that it doesn't brain crash us when we have to jump from machine to machine, or deal with compatibility and driver issues. The two forks in the road are, drag a keyboard and mouse everywhere, at which point it can be as wacky as you want as long as you can lug it, or stick to a normal enough layout you can still touch type safely on whatever happens to be plugged into the machine you need to jump on. The second camp is where I land as I can't walk into someones server room/closet and plug in some custom Datahand split keyboard and start doing emergency server administration. Back when I was doing more development work and spent 10 hours at the same desk I might break the other way. Ergonomics are about what works for you.
Funny thing is that not ONE of the linked companies currently offer a full size stick board. I'd drop 200$ cash for one that doesn't have shady closed source drivers/firmware that dial home to china and the hackable drivers a nice selling point. But instead, I am still using a 75$ amazon special because it's "good enough" and dropping on an apple or IBM layout is close enough my fingers don't get a case of "Alien limb". I have a couple "programmable" keypads that aren't nearly as useful as they could be becuase they are stuck with logitech/razer/chinesee crapware drivers.
Honestly, it would be great if there was a open source hacked driver for all those single vendor "gaming" devices, cause the phone home "cloud" crapware drivers are the worst part of what would often be some great hardware. Sadly, while a USB filter board has been sitting in my adafruit cart for a while now, don't count on me knocking one out, I just finished the last season of the Mandolorian, and after that I'm getting OUTSIDE.
But I hope these guys drop a full size IBM style, and I hope the Reg does a followup if they do.