Forrest vs Bonnar was two, regional level bums, bar brawling on Spike TV. It was an example how low the standard was on the American MMA scene was at the time and how low the expectations were from UFC fans and casuals in America. UFC was literally the Bellator of MMA at that time and Forrest-Bonnar was the most important fight they could muster.
Meanwhile in Japan you had Shogun, Fedor, Rampage, Wand and many others fighting on a skill level similar to that of today and even higher in some regards. Dana is lucky in the sense that he was strongly against the idea of TUF and instead wanted to film a realty show about his life in Nevada. Fertitas pulled the trigger on TUF and the rest was history.
While I agree the Forrest-Bonnar fight important it's also sad how shitty the UFC was around that time as a product.