They exposed the inner workings of the DNC and the Hilary campaign (same thing it turns out) and that caused a lot of bad blood in the (D) base. That caused(?) lower turn out for Hilary and possibly help lose her the election.
Basically the Russians pulled back the curtain and exposed how corrupt and undemocratic the whole election truly was and that is unacceptable.
See, this is still bad. You're agreeing that Russia had anything to do with wikileaks. They absolutely did not.
MSM is bullshit but definitely works.