They decided to leak this right now because of the good vibe Trump got after the joint-session speech.
The average American is now, so sick of the lefties/Dems spewing this crap...THE RUSSIANS ARE COMING, THE RUSSIANS ARE COMING/THE RUSSIANS ELECTED TRUMP, that they now just tune it ALL out completely.
Bingo! You're absolutely right. This is just a throw-away smear, with no relevance to objective reality, and it'll be forgotten within a day or two. It was timed for precisely the reason you cited.
The American people can see what a nothingburger this is.
What we're watching is the disintegration of the Democrat party into a petty, nasty, irrelevant puddle of impotent slime.
Any Trump supporters who are actually worried about this "story" need to have their heads examined...
BINGO!
Everything is strategic.