>>64080114ceramics, steel, UHMWPE and titanium aren't abysmal at stopping spitzer bullets, just woven kevlar. it's really bad because the pointed tip just pushes the fibers apart and slips through with minimal resistance. even against pic related in 9mm, which can defeat basically any kevlar body armor on the market. only epoxy molded kevlar helmets fare a bit better but not massively so.
this doesn't apply to just kevlar, other aramids or fiberglass or to a lesser extent carbon fiber all suffer from the same issue due to being woven materials.