With this new login system, it will help parents manage their kids’ settings in the game, such as reviewing permissions, controlling what information gets shared, and also privacy settings. As Comic Book points out, due to laws regarding privacy and advertising to children under a certain age, Pokemon GO had certain features locked out from kids below a certain age.
For example this meant that kids weren’t able to interact with sponsored gyms and PokeStops, which means that kids have less opportunities to participate in events. There is also the issue surrounding trading and friends, where those under 13 were not able to take advantage of those features which meant that PokeDexes were left unfinished.
However with Niantic Kids, it will bring some of those features to the game for the younger gamers. No word on when Niantic Kids will be launching, but if you’re a parent it might be worth keeping an eye out for.