I feel that for this the reason, telepathy is what’s needed for any civilization to transcend level 1 on the Kardashev scale. Until we can communicate more information faster than words, humanity probably won’t transcend a type 1 civilization.
There are many things for which our words aren’t enough to convey. Physical pain is one of them. There are more nuances than “dull”, “sharp”, and “throbbing”. This is one reason pain research is hard
There’s also raw speed. The speed of speech is one of the edges we have against most other species. Being able to communicate with raw thought would be even faster.
