The quandary of whether Golden Freddy is Fredbear indeed has been a hot topic among 'Five Nights At Freddy's' (FNAF) fanbase. If I timestamp it back to 'FNAF 4', where a character almost identical to Golden Freddy, a bear animatronic, turned up, it very much looked the part of a Fredbear. His appearance was synonymous with how the fan base visualized Golden Freddy - the golden bear animatronic. The teasing reveal of Fredbear in 'FNAF 4' sparked widespread conjecture that the two characters could be the same.
However, it might not be that straightforward. Though they share uncanny semblance, there has been no direct statement from the game's creator, Scott Cawthon, consolidating the two characters into one. Some believe that Golden Freddy is a mere ghost manifested by the spirit of a child given the alter-ego, Fredbear. The spectral character's behavior is inexplicable, appearing and disappearing at free will, which aligns it more with the ethereal realm than the corporeal. Moreover, the hallucinative nature of Golden Freddy's appearances suggests it's more of an apparition than an entity in the flesh and bolts like Fredbear.
At the same time, considering the 'FNAF' world's complex and layered lore, one can't discount that both the characters potentially co-exist in separate realities or timelines. A theory also suggests that Fredbear was Golden Freddy's original persona, which later morphed due to events directed by the game's storyline, becoming significantly more tarnished and ominous.
Anyhow, the crux isn't established with certainty - it's left open-ended, encouraging a wild ride of theories and anticipations among fans. I gravitate toward the idea that Golden Freddy isn't literally Fredbear but might be a twisted version or a remembrance of him concocted by the haunted spirit within. It adds a cryptic flavor, don't you think?