The Tapo L530E is an LED light bulb that is considered energy efficient, but still has an energy efficiency class of F. This could be because the energy efficiency classes for LED lamps and conventional light bulbs are different. LED lamps generally have lower power consumption and a longer service life, but the energy efficiency classes also take into account other factors such as luminous efficacy and service life.
It is possible that other light sources with comparable consumption have a higher energy efficiency class because they may have different technical specifications or efficiency features.