Ayashi99 Uh you do know that it almost certainly results in more dialog needing to be written and redone as if it was as simple as changing pronouns (via simply having a variable called p_gender set to all that you listed) then I believe that then it would have been done at the same time, however as it isn't I presume the Dev has plans for how the male and female characters to progress are different in method and thus can't be done at the same time.
Additionally what if you want to be an evil male? There choice wouldn't be there which the Dev clearly has plans for it to be allowed in my view. There will probably be choices that you decide as the player which can easily influence if they are voyeur/NTR or asexual as long as the Dev implements that.
But the key thing is that this is likely the Dev's first game although they've had an account previously and so they may not know how long of a game they can make while they learn how to make it. (What I know about game dev says that make a short game first to learn your limits and never expand the scope or overestimate what you can do) As a result I wouldn't be surprised if this game takes a year to be completed if not triple that as the Dev also has studies to attend to at the same time.
There is always the chance for yourself to do it in your own game or for the Dev to do it in their future games if they decide to continue on.