“It could be they might have warped a bit over the last few hundred thousand years. :-)”
I’ve become pretty warped in less than 60 years so it’s certainly possible. For what it’s worth the “experts” say that Neanderthal had thick shout bodies and were very strong (built like a fireplug with feet), and likely to have been ambush predators. Also those spears look like they were made from a six or 7 ft tree branch with a sharpened end. Even if thrown by a very strong arm I doubt it would penetrate very deeply into a horse.
“..I doubt it would penetrate very deeply into a horse.”
The tip can be sharpened quite a bit, and when properly hardened in a low fire or bed of coals, becomes even harder.
Not iron, but very hard.
The actual point only has to have an angle of about 45 degrees to achieve maximum effectiveness, so the tip of the spear could be nearly an inch in thickness.
Once hardened, it will easily pierce flesh and crack bones.
The spear is not a javelin, meant for throwing long distance, it is meant for close distance and when possible for hands on thrusting.
The thrust is where this type of spear is most effective.
I could penetrate a (soft) vital area 6 to 8 inches, and someone like early man or neanderthal could probably embed such a weapon a foot or more.