I started contributing to OSM recently after a bike trail was built near me. The arial imagery typically takes years to refresh around here so I walked it a few times to capture GPX tracks and then drew the new path. It was exciting to see my contribution percolate out to various apps that depend on OSM, and meanwhile Google and Apple have both ignored my edit suggestions and deny the path exists. So I have a fairly…
In a lot of areas the sidewalks and crosswalks aren't mapped even though they show up clearly on overhead imagery. I try to fill them in when I can, although this should probably be an AI task now.
I believe most consumers of OSM just discard data like buildings and crosswalks and layer on top auto traced data which has 100% coverage.