No, most theoretical physicists are not raving cranks. Theoretical physics is a field that requires rigorous mathematical reasoning and careful analysis of experimental data. While it is true that theoretical physicists may propose radical or unconventional ideas at times, it is an essential part of the scientific process to explore new possibilities and challenge existing theories.
Within the scientific community, ideas and theories are subjected to scrutiny and evaluation through peer review and experimental testing. Theoretical physicists are expected to provide a solid theoretical foundation for their ideas, which involves developing mathematical models and making predictions that can be tested against experimental observations.
While there have been cases of individuals who have held eccentric or unorthodox views, they are not representative of the broader scientific community. The majority of theoretical physicists are highly trained professionals who adhere to the principles of scientific inquiry and contribute significantly to our understanding of the fundamental laws of nature. Their work often forms the basis for experimental investigations and technological advancements.