Thanks everyone. I am late in my working career, so for me what's normal may seem different to someone in their teens or twenties. A paid-off home in the developed world has a median price around $400K, and additional savings for retirement of about the same amount seems pretty normal. So, I'm perfectly fine with people having wealth of $1M.
At $10M, we transition from comfort to luxury. A second home, or a third; expensive hobbies like sailing or horses; first-class flights and expensive hotels as the norm; enough liquid assets that you can live off of capital instead of working. When you die, there will be an inheritance that boosts your descendents. This is a level of wealth that someone could enjoy the fruits of personally. It's a problem to live this way in a world where children are starving, but maybe just over the line.
@evan an absolute dollar amount doesn’t really make sense since it’s so relative.
Personally $10M is way too much. We don’t need people with second and third “homes” (most of which are in places with housing scarcity). We don’t need first class. It also seems bad to allow a society where people can live off investment capital
@evan I had similar thoughts. I also framed my answer as "acceptable for me to have" vs "societally acceptable" - I have a number that represents financial security for life, and it's under $10M. I'd feel like I was hoarding with a net worth higher than $10M.
But I am OK with someone building a business who has limited cash flow but a net worth of $100M. I think that wealth should be subject to a wealth tax, but I also acknowledge that a 10% share of a company with a theoretical $1bn valuation is not particularly liquid - especially if their remuneration is $200k or something.
By $100M, it stops being possible to enjoy it personally. A second home is a joy, but a 10th home is just an investment. This feels like the level at which wealth stops being for personal benefit and starts being an abstract instrument of power.
To show how it could be easy to become a millionaire, even producing something useless and without to exploit workers, I usually cite the case of the pet rock.
So I think my answer is around $10M.
Quick breakdown for US people:
$1M - about 15% of the population
$10M - 1%
$100M - 0.01%