All endgame heavy armor require Elephant Hide. The issue is that currently, the only place to farm this is at the savannah around Swagger Rock. Which has no nearby Obelisks.
It’s not too much of stretch that Mammoths could also drop elephant hide, currently the only reason to kill them are for their exotic meat and thick hide (also fur), but the yield doesn’t warrant the risk, since there are much easier sources for these.
This also allows those that live in the snow biome to get additional resources, since their area is already somewhat sparse for material variety.