It’s also suspected that one of multiple purposes of pubic hair is to act as a sort of surrogate lubrication for sex. If it were just skin on skin (no addition lube, we’re talking the wild here), that would cause alot of friction leading to rashes and abrasion.
I also imagine another important purposes would be to help shade against potentially detrimental sunburns. Ouch. After all, the only reason we exist (like every other organism) is to procreate, and if our genitals are burnt, we’re useless.