>>47129959Just different meta games.
A vast majority of Gen 3 UU's best Pokemon either get really hard by Shadow Ball (Hypno, Grumpig, Solrock, Lunatone, Misdreavus) or Brick Break (Cradily, Omastar, Walrein, Aggron, Granbull).
On the other hand, Gen 4 Sneasel is most often running Ice Shard / Low Kick / Punishment or some variant on those three types and in Gen 4, UU was dominated by Pokemon like Venusaur (Ice Shard isn't strong enough to kill), Milotic (can't kill), Arcanine (can't kill), and Moltres (can't kill). Doesn't help that Night Slash was Weavile exclusive, so it couldn't benefit from it at all for some good Dark STAB.
