You have to account for the heat of the phone itself. It is not unusual for CPUs to operate at 90 degrees celsius. Modern phones have a lot of power, generate

You have to account for the heat of the phone itself. It is not unusual for CPUs to operate at 90 degrees celsius. Modern phones have a lot of power, generate a lot of peak heat from their SoC but has the worst possible cooling scenario - held near hit skin, covered in leather cases, etc. When you start at 35C you only have 25C left until the mentioned 70C, which components near the SoC Would quickly surpass. Higher rating is unlikely to help much - you need less heat generated or better heat dissipation.