That stress/strain curve in the Cell Matter "Graphical Abstract" is garbage past the point of peak stress. If it's tested in their double shear jig as shown, once it displaces significantly (> radius of the nail) the force is more the pull-out force, basically just the friction between the hole and the nail surface. Or, the nail might just be digging an oblong hole in the shear jig. It's maybe interesting, but a regular stress/strain setup is better to lead with.
The Nature article has some normal stress/strain curves which show brittle failure https://www.nature.com/articles/nature25476/figures/6