If the person referred to clearly minds, that is one thing. If they clearly take it as a joke, and reply in kind, that is another, and anyone turning it into a cause for an argument is just interfering for their own satisfaction, not to help the "victim".
Among real friends many a jocular reference is neither meant nor taken as a genuine attack. Online and read by those who don't know the individuals concerned, it is not always easy to distinguish one from another, but I would always be wary of demanding an apology for a comment to anyone but myself.