You are showing theory, experience shows something else. Something is definitely wrong with current system, people are not blind. I personally think that number of rolls maybe are increasing but probability to actually get something from these rolls is decreased. There is logic behind it. You are a winner, other have to catch you and therefore other actually have higher chance to get AM. Or purposely to be the strongest player in alliance to get most AM and therefore you actually are getting less.
Huge problem is that all these beta testers are actually top players. It is completely wrong. Top players are giving feedback about game These folks are out of reality, they have no clue what means to play with 5* 3/70 heroes for months and months. They have no clue what means that half of alliance sometimes is active, sometimes very passive. In beta testing they are trying out maxed out heroes, alliances are active and in the end we can see wrong feedback given about new heroes and almost all new changes favor to top teams. I don’t want to go deeper because I already started off topic.
In top alliances players are much more equal, almost every player can get A+ and A grade. In most alliances situation is completely different, players are very mixed, from p2w and very active to f2p and not that active. It is easy to say - change alliance. For example I’m Latvian and we are not able to make very strong alliances. Game has very poor communication tools. It is my choice to stick with my country men, true. But why I’m punished for that!? Game supposed to give us fun but somehow in some way we are loosing fun.