One could read the comment summarised by "what's the point?" as itself an idea that could change a life.

Towards the negative mainly but also maybe towards stopping negative behaviour or thoughts. "Why care?"

Nihilism is an idea that has changed the world.

The rest of the comment is more of a modern idea where no one is able to know anyone else, prioritising the individual over all. This is most common in identity politics today.

It's worse than nihilism and it also changes societies and people as it encourages and demands the rejection of understanding and empathy.