This is where Strava is interesting because of how fine grained the data is. You can reasonably assume that a place frequented by road bikers is an acceptable

This is where Strava is interesting because of how fine grained the data is. You can reasonably assume that a place frequented by road bikers is an acceptable surface for electric scooters, or wheelchairs (the surface only, not necessarily an appropriate setting). A well worn path will show many walkers and runners, but almost no road bikers. I'm sure there's all sorts of accurate inferences that can be made from the data.