18 WPM would make me feel like a snail. However, I feel fairly confident that within 1 - 3 decades some kind of BCI will let any user surpass the equivalent of 200 - 300 WPM after a bit of training. And hopefully even with a device that sits on your head rather than in your brain.
So I'm just kind of looking at this like ML research circa 1990. We're hardly even in the infancy stage yet.