I noticed that when I used one of these OSM based nagivation apps (I forget which one now), it suggested I leave my house by heading over my retaining wall, driving down a wooded hill, through a swamp, and then onto a nearby road. But because it was OSM based, I was able to discover the problem, fix it, and then when the app updated their data, the issue went away.

I have since noticed, to my frustration, that whatever map data Uber uses has the same issue, and will send Uber drivers to this road behind my house that doesn't actually have any access. Trying to explain this to Uber and get it fixed is basically impossible.

Yeah, especially accessibility-related data (especially especially crosswalk info) is apparently sorely lacking in OSM, given that every time I fire up StreetComplete in a new place the vast majority of the questions are things like “Do both ends of this crosswalk have tactile paving?” or “Does this crosswalk have an island?”.