She most likely will not get nerfed if her play rate and win rate stay the same. If her play rate rises and her win rate stays the same then she could get nerfed. This happened to her before a few patches ago along with Lux a few months ago, they were both reaching 55% win rate with a pick rate of over 10%.
The reason I think Anivia is a good pick right now is because of her wave clear along with the fact that Anivia has a high learning curve so those who have mastered her dominate games a lot more due to the potential of her wall. Her passive is also great at all stages of the game and can really turn around fights if people jump on her assuming she doesn't have it up.
To go along with her E damage, Thunderlords adds a lot of damage during trades making her able to do a respectable amount of damage with only a tear, this makes the opportunity of fighting her while she has a tear and no "combat stats" completely disappear.
Overall I don't think she will get nerfed, I'm pretty sure Riot nerfed her 3 or 4 patches ago. There were some experimental changes on the PBE a few months ago encouraging players to hit a Q or fully charged/grown R, but as far as I am aware they were scrapped.