While this is more for “routes” than proper trails, steep loose terrain has always been perplexing for me in YDS. This does occur on some abandoned trails with horrible visibility that have slid out, and is similar to the tops of some trailed passes (the east side of Franklin pass in Mineral King iirc). There’s an established route/trail near Bariloche that had a nice boot ski on it.
On one hand, it’s more surefooted_hiking despite the lack of obstacles / being very smooth just due to the slope and the fact it’s a bit beyond what someone will normally do on trail. Heel plunges, sidesteps, avoiding rock under/around sand, zig zagging to reduce erosion impacts / not be below something collapsing etc.
On the other, poles are VERY helpful going down this, especially with a full pack, and poles are essentially an arm extension. I personally lean towards this type of terrain into YDS 2 (which would be T3 / use_of_hands / hands_for_balance).
These are two very “smooth” examples.
These two are less smooth.
Having an example photo of this along with the more typical “some talus to hop” would be useful I think (along with a steeper slab route, outlined in the post above, which is pretty smooth but IMO definitely above T1 / attentive_walking). These use cases are why I mention slope itself as a potential obstacle in use_of_hands.