By the time Hearns fought Barkley he was clearly beginning to slide, his performances were beginning to look uneven. And Hearns was trying to kill Barkley with his shots in that 1st fight. He wasn't thinking about a dec.
It's funny how opinions and shifts of what is perceived as a common base of knowledge comes and goes. I remember at the time it was such a "thing" that if you had the temerity to suggest any other fight in history was better than Hagler-Hearns you were very literally burned at the stake. I saw it happen constantly. Now, people almost poo-pooh it, as if it was nothing. I suppose I too have now seen enough great fights to think it ranks lower than a lot of them, though the memory of listening to round-by round updates on the radio is still one of my fondest early remembrances of the sport.