She has spent years building up TY and IG based on others watching her and engaging with her, if your content is about your weekly shop, what you’re eating etc then people will engage with you about that!!! It’s not rocket science
Don’t want comments about it then don’t post it, simple. Also did she even think about that person and what being scolded on the internet could do to their mental health? It could send someone over the edge getting a message like that. Such a nasty thing to do. I hope she DM an apology