Russia did not do this. They own Nordstream, and are the only ones who can put gas into it, or make money from it. They would sabotage adversary assets. See (9/28) Who Sabotaged Nordstream Pipelines?
The popular misattribution results from the intrusion of the habit of the political “blame game” into the sphere of security. It’s a bad habit that could be costly in the future. There are enough reasons to hate Russia without it.