If there's no study in either direction, I rely on established industry chemistry knowledge.

1) Batteries degrade more aggressively the hotter they get. Fast charging and wireless charging make the phone far hotter than trickle charging with low wattage USB 1.1 chargers. (It compounds further if charging during graphically intense games, 4K footage, camera use, and other taxing activities. Charging in hot direct sunlight worsens it too.)

2) I always use my phones longer than 4 years, and my battery life at the end of that period still beats friends' phones with higher base capacity that are just 1 year old. My trickle charger, combined with avoiding charging past 80%, or dipping below 40%, has kept my phones functioning as if brand new. (I upgrade only due to ceased manufacturer security updates).