I’m about to get back in the market myself. I have wanted a carbine chambered in 9mm since I fired one a couple of years ago. Other things in life intervened, and I sort of forgot about it until recently, when it just poppedback into my mind out of nowhere.
At some point, most of the people who want to make a purchase will have made one. That will hold them for a good while. Not every owner is an enthusiast. Demand will probably come in waves.