The goddess does seem out of touch, but could be just as simple as her having a hazy sense of time due to being immortal. Those two kingdoms might have been good friends....centuries ago or something.
But more than that, I suspect she doesn't really have a good way to tell what's going on in the world without her saints. She knows everything about her saints, like the fact that Jelly is a slime-human and all of her likes, verbal ticks, etc. But she might be constrained by them as well. It wasn't a given that the original Jelly would grow up to be a tyrant, and once she became one, she refused to listen to the goddess. Previously the goddess appeared to have a trauma about her saints not co-operating because they're not satisfied with something. Why? Perhaps it effectively makes her blind and trapped if her saints don't work with her.
Maybe the saints are all she can 'see' very clearly in the world. She can vaguely sense certain things like the barriers and seals because they have the power of the saints imbued with them, and she can also sense things like the calamity. But stuff like politics, important figures, etc, perhaps these are things that her saints tell her directly as time goes on. So she might be really, really out of date. Because no saint has had a 'revelation' this generation except for both the original Jelly, who was a dud, and the current slime Jelly.
