If you go to the hospital for a diagnosis, it will be what you call turbinate hypertrophy, which will not directly lead to mental retardation and idiocy. However, I think there may be indirect effects. For example, long-term blockage of the nose and poor breathing will inevitably lead to changes in breathing habits, such as breathing through the mouth. If the nasal congestion is serious, it is likely to become a habit of breathing with the mouth, which will lead to a decline in breathing safety. The other is to breathe through your mouth when you sleep at night, which is very dry in the morning and affects the quality of sleep. In the long run, it is very bad.
I suggest you treat it as soon as possible, otherwise the longer it takes, the easier it is to cause other diseases, and the earlier it is treated, the easier it is to cure and the better the effect will be.