OpenStreetMap Data Working Group here. slice0 is wrong, fortera_au has accurately reported the general consensus in the project - we do not use third-party sources unless permission has been given. If you wish to use someone's video on YouTube to add speed limits then you have to obtain permission from the maker of the video. Copyright law is not always crystal clear, and OpenStreetMap prefers to err on the side of caution. Taking a careless attitude towards copyright could open up downstream users of OSM data to copyright violation claims and hence damage the standing of OpenStreetMap. (DWG Ticket#2024012310000196)