I’ll give you a use case. People with disabilities who can’t use the keyboard. Ploopy stuff has been absolutely amazing.
Probably my lack of imagination, the article is about desk setup, and while you can move a trackball with basically anything that has friction, a trackpoint is a lot smaller and finicky. A joystick could be a better version if we're thinking adaptive input.
https://keychron.co.jp/pages/nape-pro
Anyone wanting one that could fit anywhere on any side of a keyboard could be interested.