Actually, there are around 48 pages of changes for A21.
But more than that... players only look at what's "apparent": it's like they're looking at a car, and they only see the color of the paint and the interiors... but the car has been improved on the engine, suspensions, fuel efficiency, and so on... For example, they don't consider all the changes and improvements to the Random World Generation, or the optimizations to the AI, or simply even cleaning up the code to be more maintainable in the future. That's all mostly irrelevant to them.
Most of them want new guns, new vehicles, new zombies. That's all they want and look for.