If someone has a problem with idea development because they decide early that the idea isn’t worth exploring, perhaps due to low self confidence in ideation etc, then simply producing the feeling of it being a good idea could help them go further than they would otherwise with it. Of course it also makes dumb ideas feel like good ideas too, so for someone who doesn’t have the capacity to have good creative ideas or who doesn’t have this problem in the first place, it probably won’t help.
And with nightmares I’m not referring to bad dreams in general, but to horrific nightmares where a person is re-experiencing their trauma in various ways, not necessarily remembering their dreams afterwards.
Imagine sleeping eight hours but waking up more tired than when you went to sleep and in full panic mode without even knowing why. After months and years, it gets pretty tiring.
Being able to not be afraid of going to sleep is a lifesaver and can keep those people functional in their lives.