I think it's a close call, and if the institution was not rotten, the recusal would have been inconsequential.
McCarthy also points out that Rosenstein broke the special counsel regulations in order to appoint Mueller. This is certainly true.
The point of recusal is to comfort the public that the decisions and institution are straight arrow. Recusal was abused by the coup. Heck, every legal widget they touch is abused. The law is a powerful tool -- maybe it ought to have less power.
Interview with JohnHereToHelp re the thousands of hours of recording he claims to have
I have no idea if this guy is legit but you can hear him for yourself.
https://www.youtube.com/watch?v=qkmGIUWCw7s&feature=youtu.be