Beyonce is not the downfall for every other female musicians, I hope you're trolling. From not being the same type of music to hitting her peak 10 years after lauryn smashed the Grammys...stop
Anyway, this thread answered it:
- the allegations of ghostwriting
- she felt out of control of her image (read an interview in like 03/04 where she talked about not being able to pick up her baby after makeup and word rob was done, people scheduling crazy shyt like eyebrow arching in her "down time", etc) she's not built for fame
- not putting out a legit follow up, I still don't think she has a true second album. People got tired of waiting on her, she was the original Detox
- the crazy relationship with Rohan, drained her artistically and helped make her crazy, in addition to her female fans looking at her like

while she was chasing this dude who dogged her out, it's akin to the way women looked at Alicia keys after swizz
- the ego driven performances: showing up late or not at all, butchering her songs into unrecognizable renditions, etc