Pretty much nobody would use that on a standalone keyboard either. They had to know the design isn't practical for the stated purpose.
However, it does make a nice little trophy/trinket. It's merit based, so getting one could become a goal for contributors. It's branded. It fits on a desk.
If they made it twice as big and called it a trophy, it'd probably make more sense. But then costs would be higher and it'd be more formal.
Look up "artisan keycaps". Not only do people use them, they collect them, and certain specific rare and desirable artisan keycaps can be worth a lot of money. The high quality ones tend to be cast out of resin in small batches (sometimes literally just 1 in a given color/sculpt combination) and sold in short-duration raffles. People tend to put them on less-used keys.
The design of that keycap on the other hand is ridiculous.