That would be my guess. Personally I just plug my phone in and charge to 100%, albeit with a slow charger. I also abuse the battery by using my phone for navigation, so it'll often be hooked up to a charger in the car. My Samsung A52 lost a whopping 3% battery capacity in 3.5 years.

Charging to 80% would often not be enough to last the day, especially if I had to charge it before hitting 20%, so I'm perfectly fine with losing a percent capacity per year. By the time the battery starts to become noticeably bad my phone will be out of software support anyway.