Interesting.
DD would have preferred more academic challenge in kindergarten. However, I know she would have much preferred to play with the many toys they had in the room, or play outside, or read books, or do arts-and-crafts, than sit and listen to the teacher go over the alphabet for the Nth time. Because at least she would have been exercising her imagination and social skills.
Formal academics (in my mind, at least) usually involves sitting still, being quiet, and listening for longer periods of time. Five year olds are often not ready for this. They need to move and talk and explore, not sit and listen all day.
Maybe the answer is that only a fraction of KG should be academic, but that the academic fraction should be at the right level for the children. There is no point in drilling a fluent reader in the alphabet or teaching a child who can count to 100 how to count to 10. This suggests readiness grouping even in KG, which is contrary to the philosophy of many educators.
