In short, yes. Brazilian Jiu-Jitsu (BJJ) is often considered the most effective martial art for self-defense. The art focuses on ground fighting and submission holds, which can be useful in real-life situations where the confrontation may end up on the ground. It emphasizes leverage and technique, allowing smaller individuals to defend themselves against larger opponents. However, it's important to note that self-defense also involves situational awareness, de-escalation skills, and understanding legal implications to physical confrontations. Combining BJJ with other disciplines such as striking, wrestling, combatives or Muay-Thai can be extremely beneficial and provide a more wholistic approach to your self-defense journey.
Remember, while BJJ is an excellent tool for self-defense, a comprehensive approach that includes awareness, communication skills, and legal understanding is essential for personal safety.