The Sheffield / Ingle style of fighting ?

Well you obviously must have missed the fact he fought Des Gargano..

 

Hamed won his world title aged 21 in 1995. He Ko'd 3 champions and beat the other.
Of the ATG's you mention, Marquez didn't win a world title until 2003 (after Naz had retired).
Morales didn't move up to feather unitl 2000 and Barrera didn't until he fought Naz.
As I've said, Naz was ringside in 96 in Florida trying to make the Barrera fight. Barrera lost to Junior Jones and then lost to him again in 97.
At the time Naz was without doubt the top featherweight in the world and a superstar. Barrera wasn't the top super-bantam.

Naz never lost with Brendan Ingle. Johnny Nelson won the world title in 1999 and reigned for 6 and a half years before retiring due to injury.
If the Ingle style was exposed at world level, please name me a trainer whose style wasn't exposed.