Let me turn the question around on you.
Can you cite any examples that American/Western developers had greater numbers of commercial and critical successes from the 8 bit era thru the N64/Playstation era? Because as I repeatedly mention that this started to change at the turn of the millennium, these are obviously the years I'm refering to.
From the NES thru the N64/Playstation era, Japan dominated the video game industry. At the turn of the millennium, this began to change with the PS2/Xbox/Gamecube era. The question of who dominated (aka had more critical and commercial successes) is probably questionable, although I personally feel that Japan was still slightly edging out the west during this era. And now, in the current console generation, it's clear that the West dominates. This is all I'm saying.