iPhone 12 mini: 6 months old battery health drops 1% per week. Apple: totally fine!

I've bought the iPhone 12 mini since it was released. In February 2023, I replaced the battery before the price increase. I remember the battery health was 86% before the replacement. I was very happy with the battery life until the battery was replaced. Battery health remains at 100% until June 2023, then drops to 99%, and suddenly drops to 96% in July 2023, then drops 1% every week.

Apple told me they expect battery health to drop 0.5% - 1% per month. 4% per month doesn't seem normal, but I have the option to replace it with the cost.

Does it make sense?

Is this an Apple trick? Like they used to slow down old phones?