Note: the question was "Is the mean household income in the USA $140K and mean net worth $800K?" when I wrote the below answer. See edit history of the question.
In the 4th quarter of 2020 the net worth of US households was $122,886,624 million.
The number of US households was 128.451 million.
Therefore, the mean net wealth was $956,681
Total personal income was $19,502,071 million.
Therefore, the mean income per household was $151,825.
In Andersen's hypothetical world where all households have the same wealth and income, the median income/wealth is the same as the mean income/wealth (this is a simple statistical consequence of a symmetric, flat distribution). So the published claim about median income is broadly correct.
(In the above "income" is much more than salaries, profits, interest, dividends and capital gains, for example "employer contribution to government social insurance", and net payments from "social security", "medicaid", "medicare", "unemployment insurance", "veteran's benefits", etc., while personal income taxes are not subtracted out.)
