Excerpt from a Daily Beast article:
“Exposing the identity of the whistleblower and attacking our client would do nothing to undercut the validity of the complaint’s allegations,” said Mark Zaid, one of the whistleblower’s attorneys. “What it would do, however, is put that individual and their family at risk of harm. Perhaps more important, it would deter future whistleblowers from coming forward in subsequent administrations, Democratic or Republican.”
Like they would ever protect a Republican anybody. CNN proved that they are willing to dox private citizens for making benign Trump gifs. Like that didn't put that individual at risk of harm. Julian Castro released the names of Trump donors on Twitter to intimidate and incite.
Leaking info is their own game!