A champion with a point-and-click CC that allows him to take the enemy champion places sorta deserves a nerf...similarly, a champion who can poke, sustain, burst, and escape via an almost CD-less dash also kinda deserves to be removed from game...
There was no nerf to the ult, they removed important parts which made him who he was, they removed energize and his damage. He doesn't hold you long enough to drag you that far and he isn't Vi or Warwick where he jumps at you from across the map to do the suppression, it's actually not that strong of a move, it's scales with movement speed which he is kind of good for but to use it at a high movement speed it means you can't use W to get near the person, aka they should never get hit by it. The best part of that move is it's aesthetic value.
The real important part to the champion was the dueling parts, the damage was important as it is to all Fighters, and his passive Energize was what made him who he was. If you wanted what he is now, Warwick does the suppression and durability better, and Braum does the stun passive and durability better. There is no reason for current Skarner to even exist, old Skarner was a champion of his own which unique itemization and a fun and thought requiring playstyle. He was also a capable champion without the help of his team.
New Skarner is just a mash up of a bunch of tanks nobody plays and their shitty abilities. If nobody is trying to play Braum in the jungle why make another champion to be jungle Braum, especially when it means sacrificing the most fun and underrated champions in the game. Yea people didn't understand him, neither did the Rioters who did either of his reworks, but for those who did understand him he was a perfectly fine champion.