I think Diane Sawyer was a better anchor than Brian Williams. She has had a great deal of experience, both politically and as a reporter. I'm not saying that Brian Williams is a bad anchor, because that's not the case. However, she's broken some barriers for female reporters, and has a had a long and varier career.
No, Diane Sawyer was not a better anchor than Brian Williams, because Brian Williams just seemed more professional and authoritative. Also NBC has a longer-lasting reputation for better news delivery. Sawyer was a nice person, but she was too friendly, and that isn't the best for television news. Williams just presents better on television.
In my opinion Brian Williams is more likable and just more friendly and comforting to watch for me. I also think Brian Williams has a better sense of humor than Sawyer. I don't dislike Diane Sawyer and think she was a good anchor but I definitely think Brian Williams is better.
While Diane Sawyer was a good news anchor she just could not match NBC's Brian Williams. Sawyer never seemed to connect with the audience, while Brian Williams seemed much passionate about his job and did a better job connecting with viewers of all backgrounds. Overall Brian Williams was the better anchor but its not to say Diane Sawyer was bad.