It's been a while since I saw the movie. Who was injured by splinters? Were any of them serious?

The debate rages on whether splinters would cause serious injury during an age of sail battle. I found this quote, "that wounds caused by gunshot and splinters were grossly contused (injure without breaking the skin, forming a bruise) but not gangrenous."

Journal of the Royal Society of Medicine Volume 78 September 1985 753 Some forgotten contributions of naval surgeons'

It’s harder to answer “why didn’t they” type questions.

One reason sailors had no armor is that a ship’s crew had to purchase their clothing from the purser on the ship. Most sailors had no money so the cost was often an advance on their wages.

A helmet and armor would be a large and unaffordable expense relative to the “slops” they wore made of coarse sailcloth.

*Ships are dampened regularly with seawater making maintenance of metal armor a challenge. *No body armor is protection from a cannonball or chain shot projectiles

A source on English Naval practices: Shipboard Life and Organisation, 1731-1815, Lavery