That’s going to be one of those things which would need to be demonstrated on a case by case basis. Does being an asshole make him biased in a case on corporate law? Probably not. There could be cases where such a display might be used to question if he should recuse himself, but it’s going to be much harder than “I think a reasonable person could question his impartiality”. Honestly, if my lawyer was planning on that to make or break a case, I’d go find a new lawyer. Really, the interesting part of that code of ethics is the bit around political activities and the limits placed on the court and it’s staff. Though, even those have been severely weakened for lower courts, where the limits are actually enforced.

And, as has been noted about the code, it’s really just a paper tiger.