When Elisha is jeered by youths, he is at the beginning of his ministry which lasted approximately 50 years and so seemingly fairly young still. He is jeered, however, for being being bald. Did he happen to have the sad misfortune of early onset male-pattern baldness? Or was his baldness perhaps a sign he had taken on voluntarily like in Acts 21:24 or some of the medieval monks and Eastern church?
The Hebrew word translated as "bald" as in II Kings 2v23 is used in only one other place in the Old Testament:
Lev 13:40 And the man whose hair is fallen off his head, he is bald; yet is he clean.
This is clearly referring to male-pattern baldness and not a shaved head which was associated with taking a vow (e.g. the Nazarite in Num 6.)
Apart from completing the Nazarite vow and certain cleansing rituals, the Law instructed that the people were not to routinely shave their heads e.g. Lev 21v5.
A full head of hair was thought highly of in Biblical times just as it is today. The fact that youths were jeering at Elisha's misfortune perhaps shows that he had some respect to earn in the nation. He claimed to be Elijah's successor and that his master had "gone up". Not everyone believed that claim.