Some of the issues derive themselves from public mediums, aka movies, posters, magazine covers, commercials, etc... The fact that women and men see the world and communicate with the world in different ways... Many of the times, with female protagonists in adult/erotic visual novels/games they are seen more as sex objects by the male author/s and/or developers who only see a woman's perspective based on their experiences with those same public mediums... That or they have in their minds eye, this idealized male perspective of what they wrongly perceive as a women's perspective based on their idea/s of what they feel and how they react...
I know the book is old, but if you've ever read any books on the subject, such as Men Are From Mars, and Women Are From Venus... It is pretty clear that most men don't see things the same and/or communicate in the same ways as women do... And it is even more complex when it comes to how men communicate with other men, and how women communicate with other women... That perception and language barrier presents itself in fiction all the time... And it's only worse when trying to tell a story or make a game with lots of sex in it, since that same barrier and/or misconception carries over into the story telling...
Not all, but in a lot of female protagonist erotic/adult visual novels/games you get a woman character who is highly sexual, and especially in a corruption story where the protagonist is the one being corrupted, you see a lot of hyper sexualized scenes involving the protagonist... Add to that, their personalities are not always within the scope of reality... Mostly because the story tellers plans are for the character to be taken advantage of by the other characters, or to constantly present choices for that to possibly occur for the reader/player... With the aim of just making it more masturbation worthy, rather then to tell a meaningful and or realistic story based off proper female mentality/behavior...
There are some female protagonist based visual novels/games where it is more realistic for the female protagonists choices and story, but it's rare... And I think that it's either due to the author/s being male and not being mature enough and/or experienced enough to know the true inner workings of the female mind/behavior, or they just don't care and want to make porn... The few female author/s and developers that decide to make a female protagonist have the same quandaries to go through... Make something more porn based with no grip on reality, or make a meaningful story told from a true female perspective and hope people play/read it...
Another issue you run into, is that not every player/reader of items from this industry speak up in places like this or on other sites related to this industry... Only a minority of the total player/reader base even reads or posts to any forums revolving around erotic/adult based visual novels/games... So you get a very skewed and chaotic view of what folks as a whole even want from these things a majority of the time... Personally, I think the majority of folks want something with depth and meaning that sometimes they can masturbate too, but it's not always the priority... Where as a minority wants to just masturbate as much as possible and move on... Because why read a story driven visual novel which is very akin to adult romance novels, or play a story driven game which requires some reading, if all you want to do is masturbate? Hell, there are more porn videos and/or short porn stories on the web then there are people on earth, for that... Most folks want a good story to go along with their erotic stuff, because you get more pleasure out of it when it's meaningful, deep, and immersing... And it's boring to always read something told from a male perspective every single time...