The idea of a margin of safety, a Graham precept, will never be obsolete. The idea of making the market your servant will never be obsolete. The idea of being objective and dispassionate will never be obsolete.
Nature hath made men so equal in the faculties of body and mind, as that though there be found one man sometimes manifestly stronger in body or of quicker mind than another, yet when all is reckoned together the difference between man and man is not so considerable as that one man can thereupon claim to himself any benefit to which another may not pretend as well as he.