I'm tier 11 currently and i do have problem, they just don't drop enough even for abovementioned witch which rarily die.
Are you not finding tier 11 maps or not finding maps in general? They've clearly got some issues here since some people are experiencing this so I'm curious.
Come on, you quoted this part yourself in the previous post: "They don’t plan to increase waystone drop rate."
They don't want to specifically increase map drop rates but they're adding more rare and magic monsters, which drop more stuff, including maps. The 30% number is them saying that baseline maps will have approx 30% more drops in general, including all kinds of drops.
I get 3-4 t15 maps per boss and I would say about 1 t15 map per regular map so I'm easily sustaining. I agree that the atlas tree is completely pointless. The poe1 atlas tree is amazing and gives real meaningful changes to how mapping works but this tree is just garbage.
I hope for more rare mobs and I also don't care at all about magics as they are essentially just blue normal mobs.