It's not exactly the missing link, but a lot of brands have started adding features that could be seen as in between, like a little robot arm to pick things up, and little "legs" to go up stairs.
https://www.cnet.com/home/kitchen-and-household/dreames-new-...
the problem with disc shaped vacuums is adapting your whole home to make their labor saving make sense. not maps or china or all this other bs.