I think we can put a specific maximum for a comfortable western lifestyle. You can certainly argue that a comfortable western lifestyle is already far and away better than most of the people on Earth will ever see. This is something of an arbitrary point where past this, most of us are going to agree that it’s excessive.
It’s USD 10 million.
Why? Let’s start with the Trinity study:
https://thepoorswiss.com/updated-trinity-study/
The original looked at a standard retirement portfolio and asked how much you can withdraw over a thirty year retirement. It took market data from 1925 through 1995 (the updated version linked above goes to 2023) and then checked a thirty year window over that entire period with various withdrawal rates.
What it found is that if you withdraw 4% of the portfolio the first year, and increasing it by inflation each subsequent year, it’s highly unlikely the portfolio will run out in the 30 year window. The time period covers has market ups and downs, high inflation and low, and this 4% stays.
The updated study above says a 3.5% withdraw had a high chance of lasting 50 years.
Lets play it ultra safe and put it at 2.5%. With $10M, we’ll have $250,000/year to play with, and our rules adjust that for inflation.
(Median household income in Manhattan is $128k)[https://www.point2homes.com/US/Neighborhood/NY/Manhattan-Demographics.html]. We’re pulling almost twice that. I feel comfortable saying a person can live nicely in any city on this income.
So there you go: $10M. If you want a 100% tax bracket, that’s a good place to put it. Any more money past that is just a game that hurts everyone else.
Household income would be a whole family that lives together.