>>51164423It's not. Lando-T officially has the lowest usage rate of any #1 usage Pokemon in Pokemon history. At only 33% (rounding up) it has less usage than previous tier kings Tauros (100%), Snorlax (100%), Tyranitar (Gen 3 - 49%, Gen 4 - 41%), Latios (40%), Excadrill (39%), and itself in Gen 7.
It sees a lot of usage early in the generation when people are still trying to find the best strategies since it's the most reliable. When people find their footing, the #1 Pokemon's usage always drops. Well, except for the first 3 generations' OUs.