As of about a week ago all of my "Hikes" and "Walks" are showing a "Run Cadence" graph on the Garmin Connect website (but not on the app).
For hiking activities, the graph shows my cadence at around 63 steps/minute which seems low - especially given that it claims my average cadence for the entire hike is around 120spm! (Average speed is around 4mph, so the 120 is probably at least closer).
For walking activities, the graph shows my cadence at around 250 steps/minute, despite the average once again showing as around 120spm and a similar average speed to hiking.
Not sure if it's deliberate that it's being shown or not, but one way or another it's clearly broken...
Activities are tracked with a Garmin Fenix 5+ running the latest beta firmware (which I've been running for months - no changes there recently).