There are several reasons why a rock musician's speech might be persuasive. First, musicians often have a large and loyal following of fans who are willing to listen to what they have to say. Second, musicians are often seen as creative and influential figures, and their opinions may be given more weight than those of other public figures. Third, musicians may use their music to convey their message, which can make their arguments more memorable and impactful.
However, it is also important to consider the potential biases and limitations of a musician's speech. Musicians are not experts on all topics, and they may have their own personal agendas or interests that could influence their message. Additionally, musicians may not have the same level of expertise or experience as other sources of information, and their opinions may not be based on sound evidence or research.
Ultimately, it is up to the individual to decide whether or not they want to be persuaded by a musician's speech. It is important to critically evaluate the information and arguments presented, and to consider other sources of information before making a decision.