It is counter-intuitive but the axle is not holding the wheel onto the bike. That's the job of the skewer and Quick Release.
The axle is in the dropout to hold the weight of the bike from above - your photos are from below. The axle also provides support for the surfaces where the bearings and therefore the wheel run. So almost all the time, the axle is under compression forces.
Personally I'd expect to see a little more metal there, but that part should be fully functional as-is.
Possible causes its a real weight-weenie bike where every gram counts, or the wheel is from another bike/fork which had a different thickness of dropout, or its just a cheap bike saving on materials.