Why All the Hate for the Lady Ghostbusters?

I don't get it. So many old franchises are being rebooted or given unnecessary sequels. Why is this one drawing some much ire? I think I know, but I really don't want to say it. In the comment section of every article I've read about the film, you will find no end to the derisive comments. "Melissa McCarthy isn't funny." "Ghostbusters is a perfect film, it shouldn't be messed with." "Paul