The thing here is people are stuck in the assumption that there is always a global Number 1. But actually Sony were the first company to enjoy total success in all regions. Particularly the level of market share they attained.
Each territory has always had different preferences. The PC Engine was big in the SNES/Mega Drive generation and I think was 2nd in Japan with MEga Drive in 3rd. SEGA were always a much bigger presence in the West, but due to NES launching much much later in Europe than the rest of the world, Sega etc already had rivals in place.
The home computing scene (ZX Spectrum/Commodore 64 etc was also a lot more prominent in Europe until the early 90s meaning nobody ever had that total dominance and the NES never fully took hold. Likewise in the 16 bit battle in Europe. Mega Drive launched first and very successfully. SNES spent much of it's life coming back.
PS1 was the first system practically all gamers owned. Sega shot themselves in the foot with a ludicrous price tag for the Saturn, having already fumbled the Mega CD and 32X, and once again Nintendo found themselves 2 years late to the party.
But if you look at each market separately, it could well be the industry is back in transition and we can't bank on a single system being dominant globally again. Hell, looking at the gaming tablets/android consoles etc starting to launch, we could well be coming to the end of the "big three" market and at the end of the current console market place forever.
RIP Dad 25/11/51 - 13/12/13. You will be missed but never forgotten.
