One side of the slider gives a wider chest and shoulders, while the other emphasises the hips and slims the waist. Boss Factory takes that one step further, doing away with the binary entirely in favour of a 'figure' slider. In Saints Row 4, while you had to pick between ‘male’ and ‘female’ body options, these didn’t lock you out of picking any particular hairstyles, facial hair, clothes, or voices.
Saints Row has long let you play with gender, for example. As for inclusivity, things are a bit more granular.