DCIFRTHS
macrumors 68000
Sounds like your battery is degrading due to faster charging and wireless charging. Do you notice if any of these warm up the device?
Mines still have 100% capacity with cocunut showing 2800mAh, also various battery apps, compared to designed 2716mAh since got it on launch date.
I'm not the person you were addressing, but I have only used the included iPhone 5 watt and 12 watt chargers on,my iPhone 8. I am seeing worse degradation than @0014
I charge in the iPhone leather case, but there is no warning from Apple against charging with this case on. In fact, I would venture to say that it would be harder on the phone if I took the case off every time I charged it (wear and tear on the buttons).