How are they Rich if they went to Public school

I only just heard of these people on a YouTube video about influencers bragging online or faking wealth.

How can people believe they are wealthy when they attended public school? I went to a private high school that was almost 60k a year tuition (so did my siblings). We had kids of famous billionaires as students. We had President's kids as students and alumni.

No uber wealthy people attend public schools. It seems like many upper middle class or moderately wealthy people like to flex on social media (they're the same type of wannabes who join county clubs)