#4 Fans losing interest

Don't get it twisted, Becky Lynch is still very much one of the most popular entities in all of sports entertainment, but her popularity now pales in comparison to what it was at the beginning. In fact, she seems to be slowly becoming an afterthought in the division and that's certainly not what WWE want.
Maybe the lack of interest has to do with the fact that despite starting out as one, Lynch is no longer the underdog. She has proved beyond a reasonable doubt that she belongs in the upper echelon of WWE, which may be responsible for her momentum starting to trend downwards.
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Again, she is still one of the biggest entities in all of WWE and definitely in the Women's division, but she doesn't have that same underdog appeal that she did at the beginning. She also doesn't have the same big names to work off of anymore, thus another reason why fans are probably losing interest.
In the end, the lack of suitable opponents, her time as champion, and the overall staleness of the storyline are all mixing together to create a very uninteresting situation. She just isn't the same underdog that she was. She is now the establishment and fans are turning away from that.