Agree, Tyson was never the same once he lost his aura and the bully had been faced up to, although I do believe his heart had gone from the game around that time also.

Naz was never the same and only fought once after his first loss, again the aura he portrayed about being the best thing since sliced bread was gone.

The modern era has to blame in general as it's not acceptable to lose, in the 40's 50's and 60's it was acceptable to lose but as long as you went out trying. Nowaday it's straight to the scrapheap after one loss and mentally fighters find it hard to come back.