Ok here's my guess about what's going on.
Until the MC died and was reborn in this world, it was a game world utterly two dimensional and the story was "on rails".
Once she came, people behaved more 3D - with real nuance.
But everyone had a hard time dealing with their new humanity, which is why there was a bit of lag in them being nice to her.
That's all that makes sense to me. Otherwise I have no idea why people are suddenly nice to her.