PierZen
(Pier Zen)
13
We refer here to paths primarily assigned for hiking activities. Either the path I described, large enough to travel with a golf cart, or the larger one described at the beginning of the thread are for hiking activities.
In contrast, Key:highway - OpenStreetMap Wiki describes highway=track as : Roads for mostly agricultural or forestry uses
Using the tag highway=track would be ambiguous, based on the infrastructure and not the activity the the trail is designed for and some navigation tools could orient cars to such trails. Adding vehicule=emergency clearly specify an exception restricted on a very specific usage.