This the other core competence of highway=path. This the one unconditionally accepted all over the world, so it seems to me from following several discussion. Unlike mup, that is.
That was my idea when suggesting to @Tolstoi21 to create presets. Even these have to get a name. And then, they would be limited to the vocabulary of openstreetmap keys and tags. And the vocabulary simply falls short. So your suggestion to use plain language maybe a way further indeed!
Suggestions welcome!
PS: One advantage of mup : no need to tag horse=no, snowmobile=no, etc.