I have been regularly coming across a new user recently; let's call "him" Bob?
Bob is absolutely convinced of his correctness on every topic. So convinced that he answers questions using completely invalid syntax because he knows how to solve a similar problem.
Commenting on the answer and pointing out the flaws sometimes results in a constructive response but more regularly not. Any downvotes (I haven't) normally results in a semi-unconstructive comment about '"experts"' or a small lecture on how people shouldn't downvote answers where someone was trying to help and that people should learn some manners.
So far, this has degenerated once, with a different user, and the community expressed themselves by downvoting more than usual.
I obviously don't know the particulars of the banning algorithm but it seems unlikely that Bob will be answer banned. He currently has 73 answers, 6 with a positive score and 6 with a negative. Five have been accepted, one an answer with positive score, which means only 10 of Bob's answers have been considered "helpful". People seem to be more wary of downvoting answers than questions, so Bob has escaped the worst. A significant minority of answers I would normally downvote as they're just wrong, but I can't and won't do that.
I am becoming extremely wary of commenting that Bob's answers are incorrect as I can't be bothered to have an argument over it. When combined with the volume of incorrect answers this is detrimental to the site. If wrong answers keep getting posted that people are unwilling to downvote or comment that they are incorrect then they stay around. I can't flag the answers as they're just technical inaccuracies.
Is there anything that an ordinary user can/should do in this situation? Bob is obviously acting in good faith and I don't think that he should be punished for doing so.
I am deliberately not posting Bob's identity as I'd rather Bob wasn't picked on.