Attitude Era is technically a transition, too, if you want to go down that road. Before WCW started taking away talent, WWE was already pushing out the old guard and pushing the younger talent to the forefront. Bret won the WWF Championship in 1992, Bret/Bulldog main evented SS over Warrior/Savage 2 (for obvious reasons, but still), HBK's was pushed to IC level and main evented Survivor Series with Bret in 1992 over Razor/Flair vs Perfect/Savage, the rise of Razor in 1993, Flair being allowed to leave, Hogan being gone except for 2 nights, Macho being benched, the vast majority of golden era guys were being jobbed out and leaving the company.
It was clearly a concerted effort to push younger stars even before it was officially dubbed the New Generation. It was more than just a transitional period. It was an entire change in the philosophy of the company of who is and could be a star. It bled into the Attitude Era, for sure, but it shouldn't be discounted as just a simple transition. The WWF product in 1994 was significantly different than the product in 1991. It was record lows in part due to that, but also because every thing wrestling related in the US stagnated fell off huge in 1991-1992 and stayed that way until the nWo got hot.