Anti-nuclear sentiment long preceded social media and has far more to do with visceral images coming from traditional media sources around events like Cherynobyl, 3 Mile Island, Fukushima, etc.

It makes no sense to blame anti-nuclear sentiment on Russia. The evidence just isn't there, they happen to heavily benefit from it but the anti-nuclear sentiment but are not the primary cause.

https://en.wikipedia.org/wiki/Anti-nuclear_movement