Yes, the material used in the Pickelhaube are leather canvas. The material is rather expensive and it offers barely any protection. The Stahlhelm was a direct upgrade. It offers more protection against shrapnel and it’s cheaper.
The spike is to deflect vertical strikes form a trench melee weapon to the side.
The flaw of this is that you are showing your exact location to snipers, which was a big threat during the war
