>>50048448It fell off because its strongest niche was fake out + high BP moves/life orb. It wasn't particularly good in gen 6, but gen 7 completely killed it because regenerator completely ruins the usefulness of fake out and life orb Because of your nonexistent returns for spending a moveslot and item in fake out + life orb. and gen 7 and 8's singles metas is crawling with regenerator spam.
I don't know if it was ever good in doubles.
The sickle weasel idea already exists in the form of weavile and sneasel. I love all of these pokemon.