I'm not opposed to calling out shit, even in my own work, but you ought to be able to explain the smell, even if it's something silly like curly brace location. (Ideally it's shit for a better reason... there usually is.) Besides if a rant doesn't immediately follow the declaration, you can't really claim to care all that much. If you're working on the Linux kernel and get flamed by Linus consider yourself lucky! It's because he cares. (And thinks there's still hope for you to do better.)
I don't mind the rantless half-hearted calls of bullshit either; rather than leading to everyone feeling bad and trying to feel less bad by trying to make other people feel bad, I think it would sooner lead to more cynicism with insults and less taking offense and feeling bad.