What the ring teaches you is technical skills and PRESSURE this is the most important aspect of training there has to be some kind of mental pressure because the adrenaline you get hit with in a real situation can numb you easily.
But then again I'll flat out say I don't believe you can develop a technique that involves using your limb to hit someone without actually hitting something. So striking the air doesn't really teach you anything usually it ends up teaching bad form.
Throwing punches in the air. Doing weird forms of ridiculous kumite or just practicing kata with the belief that it will make you capable of ''fighting'' may make someone seemingly confident but that confidence is like a house with a foundation made from match sticks
Insert profound martial arts quotes or tough guy phrases here.