I don't play the Pokemon TCG, and most of my exposure comes from collecting cards from the first three sets when I was a kid (which I've long since gotten rid of). I decided recently to pick up a couple starter decks I saw in the store (the relevant one to this question being Mewtwo Mayhem theme deck) just to see, out of pure curiosity, how far the game has come and how much it has changed. I was looking through the cards and I noticed something odd: the Diglett, Dugtrio and Sandshrew don't have resistance to lightning, despite this resistance being a staple for ground-types. Here's the Sandshrew card pictured for reference:
I could have sworn these cards once had resistance to lightning, and a simple Google image search confirms this (in addition to revealing the cards getting HP boosts, among other changes). What gives? Why don't the ground-types have resistance to lightning? Or rather, why was their resistance to lightning removed?