The regulations on hair (both males and more commonly females) are enforced throughout your whole career.
You will loathe Raleigh if you think that having your head skinned is a stupid rule. There are so many "stupid" rules I've lost count, but they serve very specific purporse.
Lots of people in my class got put on warnings for using their mobile phone in their messdeck, people called it a "stupid rule" but again, there are times on a ship when you can't use your phone. Hence, the "stupid rule"
a. Hair. Shall be neatly groomed; taper trimmed at the back, sides and above the
ears to blend with the hairstyle. On the top of the head it shall be no more than 15 cm
in length and sufficiently short at the front and sides that when the hair is groomed and
headdress removed, no hair shall touch the ears or fall below the top of the eyebrows.
It shall be kept above the shirt collar.
In the 1960's I and a number of others on the boat I was in at the time sported Beatles style haircuts. SM2 Reggies didn't say anything, maybe because one of their number had found himself on a Boat travelling to the colder climes for being twatish about haircuts