Buddies have helped each other in subtle and profound ways for decades. Often the smallest buddy intervention averts a string of error chains occurred and negative outcomes or tragedy. The safety record of scuba diving has improved dramatically over the past few decades, while the number of certified divers has increased. During this time, buddy system training techniques have been an integral component of this training. While there is no way to quantify the accidents that were prevented or did not happen because of one buddy looking after another, empirical outcomes support the relevancy and integrity of this training.
Diving is a social activity, so the buddy system is more than a safety rule.
Diving with someone you know and are comfortable with adds to the fun. Most divers actually enjoy companionship in and out of the water. It is fun to share exciting adventures and experiences with others. Fundamentally, the buddy system is about dive companionship, something that won't appeal to misanthropic personality types. Yes, but let's be clear about what responsible solo diving is and what it is not.