All of that was based on the opinion of a private organization. No intelligence official ever had possession of the server or was involved at any time.
Do you think it's prudent for the intelligence community to allow private organizations to attribute nation state attacks on their behalf without inspecting the evidence?
It's a pretty simple question, and that's what it boils down to.
Here are more details and evidence if you are sincere and want to dig deeper: https://www.intelligence.senate.gov/sites/default/files/docu...