I'm not sure what your beef is against that trivia about the Bimbettes being more beautiful than Belle, but really, that is technically the case, at least in regards to physical beauty. Now, overall beauty (ie, far more than external), Belle is definitely more beautiful, but physical (external) beauty, well, sorry to say, but the Bimbettes have her beat, even if you leave only one of them in comparison. The standard of beauty is far closer to the Bimbettes than it is to Belle, and I'm not talking about their hair color as much as their overall body (ie, being voluptuous). To give you good examples of what I mean by this, we've got most of the girls in the Dead or Alive series, who were obviously designed with fanservice in mind (and let me point out that of all the female characters, only two, Rachel and Helena Douglas, actually stand out as natural blondes, three if one counts Marie Rose. Kasumi and Mila are Redheads (although the latter's most likely dyed), Hitomi and Lisa are brownies/brunettes, Christie, while technically a blonde, was white-haired by the time of her debut, Tina's a dyed blonde, Ayane's purple-haired, and the other characters are dark haired), and only one of those characters, Marie Rose, was not voluptuous by any stretch of the imagination (heck, she's flat-chested, and was more designed to highlight cuteness, apparently for the prepubescent little kids). Then we get into Love Hina, where with the exception of the ones who were clearly children during the events of the manga and possibly Hanako (though some stills have begged to differ), virtually all of the female characters were voluptuous, and only one of them, Mitsune, was blonde. Something similar exists with Battle Vixens. And Samus Aran's almost of the same build. Heck, May from Pokémon, despite being 10 years old, was given a voluptuous body, certainly compared to most girls her age. Now, you might think that since all of these are from Japan, they might not count due to different cultural standards. However, there are examples of this here in the West as well, such as Barbie and related dolls, as well as Lara Croft from Tomb Raider (and she's a brunette). Do I necessarily like that this is the standard of beauty? Not necessarily (although admittedly, being a heterosexual male, I'm naturally hardwired to be attracted to girls), but nonetheless, there's not much I or anyone else can do about it can do about it. Only ones who manage to be beautiful without a voluptuous body are Ariel, Brooke Anne Smith, and Snow White. Anyways, that's pretty much what I can tell you.
EDIT: Heck, regarding Helena Douglas, she looks like she could be one of the Bimbette's long lost sister, since she looks almost exactly like them (heck, even being of French descent as well).