Languages that others don't know may mean something to unbelievers, but not to the Lord's followers. Prophecy, on the other hand, is for followers, not for unbelievers.
If that happens, the master will come on a day and at a time when the servant least expects him. That servant will then be punished and thrown out with the servants who cannot be trusted.
We also understand that it wasn't given to control people who please God, but to control lawbreakers, criminals, godless people, and sinners. It is for wicked and evil people, and for murderers, who would even kill their own parents.