Juli Clover at MacRumors:

With the iPhone 15 models that came out last year, Apple added an opt-in battery setting that limits maximum charge to 80 percent. The idea is that never charging the iPhone above 80 percent will increase battery longevity, so I kept my ‌iPhone‌ at that 80 percent limit from September 2023 to now, with no cheating.

…

My ‌iPhone 15‌ Pro Max battery level is currently at 94 percent with 299 cycles

Via John Gruber, who's stats are "max capacity: 89 percent, 344 charge cycles".

I kept my phone at 80% charge for most of the year. There were 4-5 times where I let it charge to 100% for things like camping trips or long climbing days. I never cary an extra battery (with the exception of camping where there was no power), and I don't think I once depleted my phone. With a handful of exceptions, I charge via MagSafe.

My day one iPhone 15 Pro stats are: max capacity: 100%, cycle count: 229.

Am I an outlier, or are Gruber and Clover?