I've played 3 playthroughs of this current iteration (.65) with all victory types on, and all games have ended with the Prestige victory. I won one and the other two were won by AI.
The problem here is that it's really not clear how the victory was achieved in any of these games. Instead of feeling good about any of the playthroughs, I felt kind of cheated because the path to victory is not explained well enough. To draw on another 4X that does this victory type well, Humankind, they explain quite clearly how much fame you are achieving and it's clear which actions will lead to x amount of fame.
Sorry, but this victory type is a real stinker in it's current implementation.