I think it is quite likely. The Russians certainly have the motive, the wherewithal and a tradition of hatching long term plots. The ideas the Russians practised about subversion are explained here by an ex-practitioner: https://www.youtube.com/watch?v=W2RNXxBX-WM
The video is quite long but enthralling, nonetheless. It explains the ideas that were embedded in all KGB agents and explains how you can get what you want without going to war. Basically, you get the enemy to turn on itself.
It does sound like the thing that Clinton would say and WikiLeaks has just documented it. So I see no reason to doubt it at present.
EDIT: I would have posted this in answer to the second question on this subject but I am blocked there.
It is quite frightening what the Russians are up to and have been for a long time.
► Do you think education is being dumbed down?
► Should the unelected media really be allowed to shower us with propaganda?
► Are people retreating from religion so that they no longer have a moral code independent of institutions with vested interests?
The video at 11:50 is where the speaker, Yuri Bezminov, likens subversion to a martial art where you use the strength of your enemy against him by helping any group that is moving in your direction. I think the anti-frackers would be a suitably qualified group.
Think about it. Would the Russians benefit if The West produced less gas and oil? Of course it would. It would give them a much bigger demand for their own products. So why not support any anti-fossil fuel production?
The trouble with a democracy with open borders is that all kinds of views are possible and are allowed. To be subversive you only have to support the views that will benefit you. The indigenous population will do nearly all the work for you.