Hello! I've added myself this way on the map few years ago and rode it with a mountain bike. I see that you've added the surface yesterday

With trails in nature it is a matter of subjectivity. Some people might not find it suitable for diverse reasons. many even do not find large tracks. So OSM has tags which describe diverse aspects of a way such as:
- trail visibility https://wiki.openstreetmap.org/wiki/Key:trail_visibility
- trail difficulty per activity, like hiking https://wiki.openstreetmap.org/wiki/Key:sac_scale 
etc...
So what do you mean by "unpassierbar" and "verliert sich" Are there fallen trunks?