I consider 'fuck you' money to be enough that it'll last until you die, while living comfortably. This is still an amount that you burn through in a lifetime. Something _like_ 'financial independance, retire early'.

I think the parent is suggesting a money threshold beyond which you can't really feasibly spend it fast enough (without being deliberately wasteful), so 'the rich get richer'.

No, this is "not be fucked" money. Without some minimum amount, you are fucked and will never escape poverty.

"Fuck you money" is when you can just quit your job.

"Fuck everyone money" is when you can just buy Twitter.

I was at a museum looking at a group portrait of 18th century rich people in uniform and it hit me.

Not a single US billionaire will ever have to lead a regiment in war.