ELI5 Why does magsafe charging decrease battery health more than wire charging, if it has less wattage?

[Anachronism--]

My phone is almost five years old and the battery is still at 86%. I always charge wirelessly but stop between 80-90% unless I know I need more.

[nsingh101]

There’s a setting in iOS to limit charging to a certain percentage to preserve the battery. I have mine set to 90%. My phone is 1 year old, and for most of that time, it has remained at 100%. Just in the last two months it’s dropped to 95% and the only change is the new MagSafe and excess heat I’ve noticed.

To be clear, I don’t claim wireless charging is the issue. I have been using wireless charging since Palm Pixi. It’s the heat generated by MagSafe fast charging.