I agree the “description” column in the table (which was only added in 2021 by @rhhs) is very car-centric. I don’t think the rest of the page and the “usable by” column (which dates from 2008) are too car-centric.
After discussion on the Wiki talk page, I’ve just edited the description of impassable: the 2021 description said “Ways that used to be passable roads … but have deteriorated so much … that no 4-wheeled vehicle can pass it.”
This may apply to some impassable ways, but over 60% of uses of smoothness=impassable is on highway=path and if you look at example, very often these paths were never roads. The 2021 description just confused people into thinking that impassable is inappropriate for such cases.
If anyone here speaks Hungarian, Portuguese, or Romanian: you can help by translating the new description here.