Just a thought about the true final Palace... (MAJOR SPOILERS(I think, just warning either way))
So, I guess this is technically about religion, but if the shadows and the final boss were based off of Christian figures, like the God of Order and literally all of the angels, then wouldn't it technically be demons vs. angels? Is this a callback to SMT?? Either way, I had this thought throughout the entire palace... But the boss uses the Seven Deadly Sins against the Phantom Thieves, so would that make him a bad god posing as a good one? What are y'all's thoughts on this?
It's because of how he views humanity, given how he sees humans as feeble creatures who if given free will, will tear themselves apart, how he mentions after every sin he pulls out "will be the downfall of humanity" or something along those lines
SMT's interpretation of YHVH hasn't ever exactly been good. Though for reference, yes, Yaldaboath is actually basically a fake YHVH in smt terms so it is very likely a callback.
Actually yes, the final run towards the top of that tower is a callback to SMT1. In that game, you ascend the Basilica during the finale of the game and fight the Archangels before facing Michael as the Final Boss of the Chaos route or Neutral route, meanwhile he gives you his blessings or whatever in the Law route.
Of course, P5 forgets the descent down the Basilica and its Chaos route bosses