Mapbox styles should omit ways rated SAC scale 5 and 6

SAC scale 5 and 6 trails should be omitted from Mapbox Outdoors (not included out-of-the-box). Mapbox users that deploy Mapbox maps should have to make a conscious decision to include these trails in their maps (e.g. if they are making a specialized mountaineering map).

Trails that are tagged with a 5 or 6 SAC scale rating require special equipment and training, and novice hikers may get stuck on these trails.

Example

• This has come up with other OSM-based maps (non-Mapbox), for example here.
• Here is that trail on OSM.

Current Style Differences are Insufficient

Mapbox styles these trails differently, but not in a way that would make it obvious to a novice or even experienced hiker the trail isn't passable. There may be no style strong enough to do so.

Trails Cannot be Edited Out of the Style

It is also not possible to remove these trails using a custom Mapbox style on mapbox.com. Even if it were possible, this seems insufficient - these trails should not appear on Mapbox styles intended for outdoor apps by default, since many developers will show them without understanding the danger.

No file or test is named in the issue. Start by locating the Mapbox Outdoors style definition and its trail layer filters, then inspect how SAC scale tags are represented; done means SAC scale 5 and 6 trails are omitted by default while other trails remain available.