How come Elise isn't played much/anymore?

It's not that the meta doesn't suit her but rather she's not capable of being good no matter the outside circumstances right now. Her kit got destroyed and there's only so much a favourable meta can do to fix that.

With the buffs they gave Elise in patch 5.12 it's possible she could return, Use your Q (Human form) W, Cacoon, --> Spider form, Rapel onto them, Deal as much damage with AA and Spiderlings as possible, and on the 4th seconds pop your Q and it should be a TON of damage considering her SPIDER form will deal 100%!!! Bonus damage in spider form after repel. If you want to know where I got this information check out Pants Are Dragon on YouTube, He's a Noth American Challenger Jungle main and can Jungle just about ANYONE and even goes as far as to consider low diamond (3-5) a trash elo, He is AMAZING.