Incentives not to "talk" as well as self-willed ignorance:
Since no country is yet ruled out from having carried out the attack, officials said they were loath to share suspicions that could accidentally anger a friendly government that might have had a hand in bombing Nord Stream.
In the absence of concrete clues, an awkward silence has prevailed.
"It’s like a corpse at a family gathering," the European diplomat said, reaching for a grim analogy. Everyone can see there’s a body lying there, but pretends things are normal. "It’s better not to know."
https://www.zerohedge.com/geopolitical/dont-talk-about-nord-stream-details-wapo-report-upend-official-narrative