Crazy theory. What if personas are control mechanism? The one who got wild card is now completly controlled by the player and their life is in our hands. I know that in some Persona games, you can't control party members, from what I remember, but you still control them in some way, so the one who got persona are 50/50 in our control, like they have lives, do what they want and sometimes they are our puppets. The social links are also forced to have somewhat bond with us even small. The velvet room has long ago written the scenario and is forcing fate to play into their script and I mean players are the fate (also it's crazy that literall high schoolers can deafeat God).

I don't know I just had this thought