How to Calculate True Total Cost of Ownership for S3 at Millions of Requests Per Second

https://www.bust-bookmark.win/seasonal-traffic-spikes-when-s3-bucket-policies-beat-iam-roles-and-when-they-don-t

Which specific questions will this article answer and why they matter for engineering teams? When you operate at massive scale - millions of requests per second (RPS) - the usual talk about "cost per GB" becomes a distraction