Is tight foreskin hereditary?

No: This is not hereditary (genetic). This is an acquired condition from inflammation of the foreskin that causes scarring of the foreskin.

Unlikely but maybe: 99% of newborn males have physiologic phimosis, & vast majority will free up up sponateously with time. A number of foreskins remain tight and this probably occurs in a number of father/son combinations. Forceable retraction of tight foreskin before spontaeous resolution can lead to splits in the foreskin which scar with healing creating a scarred phimotic ring, thse are no way hereditary.