One of my programmers (a remote contractor, but FT) has taken to routinely criticizing my code whenever I touch systems that he has previously worked on, in ways that are reliably incorrect (you'll obviously have to take my word on it, but I'm pretty good as an IC, and while he is not terrible, he's just at the "passable junior programmer" level despite a decade in the field). And I mean reliably: I've never gotten a single code critique from him that has turned out to be correct or useful, and I've really tried to engage and give him the benefit of the doubt. A 0% hit rate on code feedback is almost unheard of.
His delivery is neither bad nor good, like many programmers he can be too strident and lack sensitivity, and there's a language barrier that has led to some missteps which resulted in feedback, but to be honest, if he was offering good critiques, I'd be fine with all of it, it's behavior that I encourage from others and it's extremely useful when correct. I've gone deep with him several times on the technical details, but the discussions don't lead anywhere, he doesn't appear to understand when he's wrong, or if he does he does not acknowledge it. It's never the same exact code or error that leads to his misunderstanding, but the pattern is very clear at this point, and it seems like what he really doesn't like is people touching "his" code. We've talked about how that can be a problem, to no effect, he claims it's not happening.
This happens frequently enough that it *is* causing my personal productivity to go down substantially, since it takes a lot of time and effort to evaluate and respond to his suggestions.
What is the move here? I feel like continuing to get into the weeds on the details and even spend time myself evaluating his suggestions is a losing strategy, and asking him to be more careful with his criticism has failed (he thinks he is doing that already, and I believe that every time he makes a criticism he feels like it's 100% valid). But something feels off about straight up telling him that his feedback is no longer welcome.
Do I just "your suggestion is noted" over and over until he gets the message? He has reacted badly to that in the past so I'm hesitant, but I suppose not accepting my decision is at least a concrete behavior I can address that is quick feedback rather than a drawn out technical discussion.