I really find it hard to believe that it's always Russia that's responsible for every ill in the whole flat world.
We've already had the evidence declassified that the whole 2016 Russiagate hoax was entirely invented by his opponent for political purposes, and then spin out by the media out of control. But, yeah, let's still believe each nation accusing Russia of all evil!
In the case of Norway, this could be a public signal to Russia indicating the motivation for some other action, such as the recent Su-30 friendly fire incident, the recent munitions dump explosion, dramatically enhanced IT capabilities by the Belarus opposition movement etc.
So a message: "If you do this, we do that." If the acting parties know who they are, no public proof is necessary to send the message.
The recently declassified documents in the last month or so, point to a very different picture on 2016, however.
Meanwhile, actual election interference in 2020 by foreign nationals like Greta of Sweden -- even right after her candidate has publicly denounced Green New Deal in the first debate, and after he's openly supported Fracking in Pennsylvania -- is totally okay with everyone!
Nations are really cautious about attribution. For Norway to officially blame Russia it just means they've found some pretty convincing evidence.