Beard is a by Product of the Body
Anyone with some basic human biology knowledge will know that, hair is essentially a by product of the body, just like stool.
A Bhagavad-Gita follower will not keep a beard, because he will think of it as stool on the face.
Swami Srila Prabhupada, a top most follower and preacher of the Bhagavad-Gita, instructed his followers not to keep beards.
if one cannot afford a razor or is traveling in the jungles and thus does not have time or access to water, or lives in a cave. Then it is understandable to have a beard. Otherwise one should not keep stool on the face (a beard).
Men who have taken vows to follow the Brahminical principles, should not have a beard nor hair on the head, they should be clean shaven on the head and face. Other men can have hair on the head but not on the face. The hair on the head is for the purpose of retaining the body heat. There is no need to retain the body heat from the face.
Women should not cut their hair, they should have long hair so it can be used to protect their private parts when needed, and the long hair makes women feminine, of which being motherly is one feminine quality. Women who cut their hair have the highest chances of losing their feminine qualities. The main feminine qualities are motherly affection, patience, faithfulness, fine speech, memory, and fame. The gopis are the topmost devotees of Lord Krishna and none of them have a boy cut, they all have long hair.
“..Among women I am fame, fortune, ﬁne speech, memory, intelligence, steadfastness and patience.” (Lord Krishna, Bhagavad-Gita 10.34)
It’s due to degradation of human consciousness, which includes laziness, that men are keeping beards thinking they look good. Even some women like men with stool on their face (a beard). If these women had stool ( a beard) on their face, would they like it? One should not wish onto others what they do not wish on themselves.