Its a double edge sword, you can use it very good or bad. A good writer can implement these changes very cleverly while a bad writer will fill in the story with these changes in order to compensate for their lack of story telling. Something like boku girl where gender bender is done right is an example of a good writer, at least imo. However the real idiots are the one who just hate these stuff (aka "sjw") without reason or any justification and just assumes its all bad.