Xerneas was never asked by anyone anywhere to be a character in the game. He doesn't have anywhere near the level of expectation of the ATs, let alone Ridley. And the ATs were explicitly ruled out as playable upon being posted. 100% clear. Which is why, again, the ambiguity with Ridley raises the question of various possibilities.
What does popularity have to do with the factual evidence you presented being faulty? Or, more importantly, why does it factor into the equation at all? Ambiguity is ambiguity, irrespective of popularity.
This is textbook goalpost moving.