This German language video on Stream Deck XL shows a 5x3 profile being copied for use on Stream Deck XL - the bottom row and right three columns of keys are blank.
David Tee - there have been entire keyboards with OLED screens in the keys, notably including the Optimus products. I think many of the Optimus products didn’t go beyond the concept stage, but a version of Optimus Maximus did. It was horrendously expensive (over £1000) and the technology of the time really wasn’t up to the task - OLED screens have a limited life and can suffer burn-in, which was a particular problem for a keyboard that spent so much of its time showing static images. Reviewers complained of ergonomic issues with typing on flat glossy keytops and I believe there were key spacing issues with Optimus Maximus as well. As I recall it, the keys were slightly wider spaced than on a conventional full size keyboard, causing muscle memory and hand fatigue issues for touch typists. A touch typist will hold their fingers over the home keys and will often have their keyboard placed close to them at an angle where it is uncomfortably far down to look at the keys.
Were Optimus Maximus built today, it would undoubtedly be able to leverage improvements in the underlying technologies. However, my personal view is that macro / smart launching with interactive legends is better done by a Stream Deck (or perhaps Apple Touchbar - though that lacks the tactile feedback of button edges) like adjunct to a keyboard, not a replacement keyboard. A lot of the clever functionality of Stream Deck would be difficult to implement if the interactive buttons and keys of the keyboard were one and the same - how do you overload two functions sensibly onto the same buttons? I have not seen any hints that a new Optimus Maximus type product is going to be released, but maybe others have seen something.