Why the Black Lotus Change Actually Keeps the Essence of Classic

The reason that Black Lotuses are more rare in anniversary servers than in Classic or Vanilla is that there is only one server, with many layers.

Let's say there are 6 layers on average, it's the population of 30 servers on 6 servers' worth of herbs/mines. Forgetting to increase the Black Lotus rate is basically a bug that was overlooked.