Today is the last day for weekly league rewards -> so you do not want to miss on extra legendary girl cards as reward. So naturally such players will go to league 1 (might as well enter in top 50 if you can)
I don't think that was it. I have a whole new set of opponents now and league 2 went from players with 3 to 4 times my health to players with a bit more and a bit less. Maybe it was the bots that was mentioned being removed.
Maybe you are right bro regarding AI selection BUT i am not wrong either regarding league movement and reward. We just need to see in future how AI opponent will change in future. If HP remains less than 1000K, then it is in best interest for all according to me - saves TIME.