That is much less effective than every other manner they tested on the past few years such as shadow fleets, ghost satellites etc.

Up to the moment it has not been the operation adopted which would make it weird.

On who would do it then, anyone who benefits from instability. From corporations trying to sell flocked uped sytems, politicians, etc.

There is one south american country who was attacked exactly this way before their head of the government was kidnapped.

You don't understand Kremlin's mentality. Any even little nasty thing they can do to the West makes them giggle like Doctor Evil. "Oh, a NATO country's government infra was not protected from DDoS? Let's have fun, haha!" You are dealing with story book villains. I know, this sounds so ridiculous it's hard to believe someone can actually be like this. But then the reality check hits.