I've only raided once since the Wild Growth nerf. What I discovered is while I don't use Wild Growth much, I did use it more than I realized. In other words I found myself reaching for it when the cool down wasn't up more times than I expected.
I consider myself lucky. In druid years, I haven't been resto very long. So healing spells changing doesn't really effect me as much as someone who may have relied on it for months.
Blaugust long term effect
7 hours ago