Ruinous Empathy is “nice” but ultimately unhelpful or even damaging. It’s what happens when you care about someone personally, but fail to challenge them directly. It’s praise that isn’t specific enough to help the person understand what was good, or criticism that is sugar-coated and unclear.
Ruinous Empathy is seeing somebody with their fly down, but, not wanting to embarrass them, saying nothing, with the result that 15 more people see them with their fly down — more embarrassing for them. So, not so “nice” after all.