WHO are just being politically correct. They'd never dare advocate for female circumcision even though it is quite reasonable that removal of similar cells from female genitals would produce the same marginal benefits against HIV infection (and in fact the other similar benefits attributed to male circumcision). They are also dishonestly using the most extreme form, commonly carried out in unhygienic conditions, as their example.
It eliminates bruising and tearing during sex
Maybe the good brothers should try some foreplay and avoid trying to ram the whole thing in at once.
The other alleged health benefits are at the very least wildly exaggerated by advocates. Plus there is no reason not to wait until adulthood, and very good reason, besides leaving it to personal, to wait to allow a proper accurate cut to be made instead of the guess doctors make with a baby.
If it can be allowed for parents to order surgical modifications of their male child's genitals, then there are no grounds for not allowing the same with female children. I'm sure with some research the slip-ups, like those that kill and maim a percentage of boys every year, can be kept to reasonable levels.
Which is why we need to get onto getting it mainstream for girls as soon as possible.