Oh, but it has. Long since.
https://ceratech.co.uk/collections/left-handed-1
https://a4tech.com/product.aspx?id=137
#Maltron even long since went to the extreme of doing a left-hand-*only* keyboard. No, I have no idea why the letter U gets to be special and done with the thumb.
https://maltron.com/store/p1/Maltron_Single_Hand_Keyboards_-_UK_English.html



