Actually there are people who have mined/analyzed several billions of PS hands (not millions). Don’t expect to see them posting here though.
Believe it or not but seems the players are dynamically segmented into several “player groups” by PS internal algorithm. Each segment then gets whatever PS decide the segment deserves – this includes not only promotions, free tournament tickets etc. but also good/bad pocket cards, good/bad run, coolers and bad beats, everything. The sizes of the segments are quite interesting as well, Gauss will be very disappointed if you try to convince him it is a normal distribuiton.
Then there is also the so called river card syndrome. Based on billions of hands players from the “doomed” segments are losing a lot because of the magical river card dealt. Hands where the player is >80% fav to win the hand is actually losing it in about 60% of the time due to a “magical” river card. It becomes even more insane if you remove the hands where the players are all-in at the river. Now more than 70% of the hands that go to showdown are lost by the “doomed” segment player who was ahead before the magic river. Billions of hands analyzed. This syndrome is valid only for the river card, the turn card usually works as expected, even a bit in a favoure of the "doomed".
There are few forums in the dark web where the guys are posting their findings, trading HHs etc. Go and check.