OK, you say nearly 100 years. Let's take the 20th century as an example. Bimbo refers to stupidity and naivity you say. From 1900 up to deep into the 1960's, but lets say 1965 to make things more streamlined, men wanted a naive and pretty girl who does as she is told, is being taken care of by her man, and brings pleasure to his by making his life easier. In those days it was normal to have a pretty big age difference, that way the man could guide and girl made him look good. With the hippy movement, the feminist movement was tirned into overdrive, and we see a slow transition towards a more equal relationships. Ages of partner come closer, eductaion and carreer is more important for women.
Ofcoarse there are always exceptions, and where as the woman studying or leading a company was the exception in the 1900-1965 era, it has transitioned to a woman being submissive and naive, wanting to be a good housewife being the exception. I would say Bimbo as a negative term only gained traction in the last decades of the 20th century, and doubt it was in much use before. However just because females started to rise towards equality, doesn't mean the men of the 60s, 70s and 80s changed their preferences, atleast not all. And I think for those many men who want a fun girl just as their mom had been to their dad, for them the term bimbo is a very positive one, and spoken with pride when discussing the new girl they have started dating.
We pretty much all have been raised by a generation who doesn't feel feminism is optional, so ofcoarse liking submissive women, or more important being a submissive women who wants to look good, and bring joy and pleasure to her hard working husband is pretty much not done. So the few who do like this lifestyle might embrace terms like housewife, wifey, daddy's little girl, bimbo etc. to empower themselves.
So as you see throughout the years where the word is popular, it's always been used as a positive as well as a negative. It just depends on what gender you are, who you are talking about, and what you want in life.