You're totally rightIndexing is a thing but looking at some of the graphs you guys have shared, the drain is rather drastic. Whenever I switched iPhones, the first couple of days of indexing don’t drain much. The gradient is rather gradual.
In my opinion, I think it’s part of Apple’s plan to reduce/increase battery life every other year. Before I get called out for speculation and being a conspiracy theorist, here’s what I can back up with.
The iPhone 11 Pro/Pro Max had tremendous battery life when they first came out. Best battery life ever at that point. Sadly the 12 Pro/Pro Max were downgrades in that aspect. A year later, the 13 Pro/Pro Max had major improvements in battery life. And this year it seems like we are following the cycle.
11 pro - good
12 pro - bad
13 pro - good
14 pro - bad