I don't follow this stuff closely, but I do have it in my RSS reader.
Here's someone recreating the Space Cadet keyboard key caps -- i.e. the plastic covers for the keys, not the actual keyboard. This is a more modern profile (key shape), rectangular/cylindrical similar to modern keyboards rather than the spherical top of the key like in the 1970s and 1980s.
It might give you an idea how expensive a custom keyboard would be.
https://www.reddit.com/r/MechGroupBuys/comments/j3pmmn/gb_gm...
> releasing a space cadet mechanical keyboard
The mechanical keyboard community will probably get there first.
From a quick search, I've found this [1], which goes a bit beyond the original Space Cadet keyboard.
https://i.stack.imgur.com/egD8V.jpg
That is the splash page that hasn't changed much since 2000. Reading the helpfully highlighted first menu entry do you think that Emacs has a tutorial?
Users who can't even be bothered to read the text in front of them are not an asset to a project that doesn't charge them, they are a liability since they force the project in stupid directions. The death of firefox is a perfect example.
The thing that Emacs should focus on the future is true concurrency. Nice to haves would be a non-gtk gui, adding scheme scripting support and releasing a space cadet mechanical keyboard.