It's explained in the leaflet that they automatically invite anyone registered as female to have a smear test it also says if you don't have a cervix you don't need to make an appointment if you are a FTM transman and haven't had a full hysterectomy you still need to be screened.
There is absolutely nothing to be outraged about.
Perhaps they could expand their databases to include information on whether a member has a cervix. Or testicles, or whatever relevent parts. Because that is what is important here, not someone's sex or gender. If you don't have the relevant part, neither matter.
But if they are going to go with the blanket invite approach, they should probably record someone's inferred-sex-at-birth rather than just their current gender.