On the 21″ wheels it is two fold as far as tire retention goes. Most narrow 21″ front wheels don’t have that safety bump but they also don’t have much rim depth at the tire bead to rim area so not much to retain the tire on the rim if it suddenly goes low on air.
The rims on the 800GS are pretty soft so bend easily on a rock or square edged hole therefore tubeless air loss while riding is always a possibility on those low sided rims.
The good news is; the 21″ rims are super easy to remove or mount tires on.
The bad news is; the 21″ rims don’t retain the tire very well during an air loss event.