>>35902474>>35905103levitate was a mistake tbdesu, it only fueled the "why is this floating/flying thing affected by ground moves" autism when pokemon like venomoth and magneton get hit by them.
and as the series went on, the meaning of ground type got really muddied (pun intended) by a growing abundance of the non "ground" ground attacks like mud shot that birds are suddenly completely immune to the effects of.
ultimately it's better to just not think too hard about type immunities (like ghost granting extremely selective intangibility) and accept that sometimes things just are the way they are because it's a video game