Was just there a couple weeks ago and can confirm that the lounge (BA) is truly pathetic and seriously overcrowded until 57 leaves. I originated in SFO and felt I was far better off buying some San Francisco sourdough and having a snack elsewhere where there was a view.
I connected in SFO last fall and, having seen the bad reports about the BA lounge, went to the AA Admirals Club in the next concourse. It was pretty basic in terms of amenities (food etc) but was relatively uncrowded and peaceful, which is my #1 priority in a lounge.