In the pic, the ortholinear keyboard is not the full width of the 16", so it wouldn't be anymore split than your tiny planck. A full-width ortholinear with excessive keys would be another story.
Mine is split in the sense of having the main keys in the middle of the keyboard on your strong fingers (like the old typematrix which was the first ortholinear keyboard I ever used) it’s not in separate modules like a kinesis or ergodox obviously. I don’t know if that would work on a laptop without it being excessively wide.
For my personal mix of tendon and joint problems actual separation isn’t helpful because some pronation is actually good for me. But obviously that’s going to vary.
On the Framework 16, there is unused space on each side of the centered keyboard w/o number pad. With a split keyboard module, that unused space could simply be moved to the center.
