After a talk show host smears the poor on TV, a woman who advocates for society’s invisible goes on the show to confront him then he physically assaults her, years later she struggles to help him when she discovers that he has become one of society’s invisible.

This logline is vague, which I sense you did on purpose to add mystery, however too much vagueness and it takes away from the impact of the logline.

Vague:
1: A woman, this is vague. What woman? Proud banker? Snarky babysitter? Intelligent professor?
1: Why does she confront the host. Why does she feel the need, is it personal?
2: What last words?
3: What terrible event?
4: What, ‘one thing’ must he do?

Also, who is the lead character, it seems as if the woman is the lead but it is the talk show host who must ‘do something’ which makes it seem like he is the lead character.

I believe if you add some specifics it will help the logline become more compelling.