There’s a motivational difference between persuasion and coercion/manipulation. Pointing out that an act is evil isn’t inherently manipulative, but implying shame and guilt in order to coerce someone into changing their behavior is. It’s a fine line and it’s hard to litigate because the distinction is motivational.

The thing with guilt tripping is that it tries to bypass the will and judgement of the victim and coerce them to do something against these self properties through the guilt. Calling out someone to better their behavior is an open criticism, not guilt tripping.