My mother always taught me to not make a fool of myself by talking about things that I obviously know nothing about. My wife and I have lived on a airport with our two airplanes for 25 years. We started out flying hang gliders and ultralight airplanes. Before we got married my wife socialized with both Thunderbird and Blue Angel pilots. Truth be told, she found out that in most cases the pilots did have very high opinions of themselves which is helpful for doing their jobs but can make them unpleasant to be around if you are an attractive person of the opposite sex.
Apparently, the first thing that needs to explained to you however is that big things look much smaller when they are far away then when they are up close. For instance, the airplanes that the Blue Angels fly in formation may appear to be 6 inches apart to you while watching from the ground but I can assure you as someone who has flown in formation with other pilots that our airplanes and the blue angels airplanes are much further than 6 inches apart. Compounding this, in the case of the Blue Angels, the maneuvers are carefully choreographed so that they appear to be closer together than they actually are from the perspective of the target audience.
Flying in formation has for many decades been known to be very useful practice technique both for developing skill sets and camaraderie within groups. It is also not as dangerous as you seem to perceive it to be. Safety is always an overriding concern in aviation training. If you doubt this you might consider taking some form of pilot training and then reporting back.
OK, I researched it and I stand corrected. Minimum separation in Blue Angel formations is 18 inches. You consider this a safe and necessary maneuver, perhaps. But do you know it’s forbidden to other Navy pilots? Along with a great many other maneuvers that are routine for Blue Angels, but will otherwise get you grounded? Sorry, I am not buying the “training” line.