Of course the mesh itself and materials are placeholders.
But… lot of marketplace/community animatios are rigged to this skeleton. It’s kind of standard skeleton for engine, very useful for small teams. Easy to get plenty new anims without even retargeting. And no risk that anims would be messed up on your skeleton. So it’s very useful.
If you care about quality, it’s worth to consider separate female skeleton and anims in your game. Some female anims are just adjusted male anims of course. Although often it make sens to create walking anim from scratch for woman 
2 skeletons for humans are often enough even for big RPGs (if skeletons are good enough).
Having basic male and female skeleton could be great for non-AAA teams just because it would become standard set for marketplace/community creators. This is then only but valid reason to have female skeleton.
It doesn’t matter if the mesh and materials would be close copy of original mannequin - this is just placeholder stuff.