$5.7 million in 20 year US Treasury bonds returns about 1% now. That’s 57,000 dollars/year.
Definitely not living large on that.
An additional $57,000 a year of income would certainly help get the bills paid for most people.
Or one could invest that 5.7 million, or a large part of it, in something else and get a better return than 57 thousand a year. Maybe buying rental properties.