they deserve any abuse they get

"Use every man according to his deserts, and who shall 'scape whipping"

It doesn't matter if people deserve to be abused. The abuse doesn’t actually damage them, anyway, it damages the Mudcat. Let it go. Stop responding to the person who deserves abuse in your view. Blank them for good, maybe, but don't muddy the water for everyone.

There may be occasions for exceptions, but very few, and not many people have the inbuilt acumen to do it right. The late lamented Castspaw was the only person I can remember who could manage it right.