Unlike men's bodybuilding, there is no widely agreed upon golden age for women's posing. But I think you're right, that European contests - particularly NABBA - had better posing and posing routines than the IFBB or NPC. IFBB and NPC are more concerned with being monopolies and maximizing their revenue.
I'm going to say the 90s European contests had the best posing routines. Very sensual, lots of thongs, unabashed moon-shots, and the women genuinely looked like they are having tons of fun.
e.g. this is 1992 NABBA Worlds