I think it's a combination of scare exotic materials and a reluctance to continue on with a technology that proves to be the least bit dangerous. Things like interphasing cloak with the Romulans and Klingons-they gave up on it after one ship was destroyed. Warp 10 has some mutating effects. Better not use it again.
It's an interesting attitude that is presented that keeps getting repeated down the line by various Trek cultures. If something presents as dangerous to use, even once, then it gets relegated to the warehouse of "Whelp, we tried" technology.
It's an interesting attitude that is presented that keeps getting repeated down the line by various Trek cultures. If something presents as dangerous to use, even once, then it gets relegated to the warehouse of "Whelp, we tried" technology.