According to reports, his grandmother died in March 2023 and she left an estate worth $30M. She had
10 children and 37 grandchildren. I doubt she left anything for grandchildren. Estates are usually divided amongst children, and those children can gift or bequeath to their children.
It might be a bit of a feather in his cap to brag about "generational wealth" as something that he does not respect.
Maybe his parents were due to receive up to $6M, maybe not. Numbers suggest $3M per child. Maybe the inheritance was in property, so not $3-6M in the bank. Maybe the estate is larger than reported.
Regardless, I don't believe Mangione has that much money from his family. I would like to see his personal finances from July 1, 2022 to Dec 4, 2024, to include 6 months before surgery, grandmother's death, job loss in June 2023, and his international travels.