With the right key mapping the hex grid naturally leads to hand rotation and column stagger. It also takes “1u distance from home” literally because there are no diagonal keys for the index fingers and pinkies that are 1.4u away. It allows keys to rotate in 60° steps rather than 90° steps. That allows for some interesting ways to exploit tilted key cap profiles.
I may ask the opposite: why squares? That’s just as arbitrary, if you think about it. I learned typing on a mechanical typewriter that had round keys.
I’ve done something like that with a multmatrix transformation. There is an example of doing a skew transformation like that in the OpenSCAD user manual. This works with any 3D shape, not just extrusions. So you could transform a cube into a parallelepiped.