This is subjective and depends on the cost of living of a person so you will definitely receive different answer that doesn’t give a conclusion for this generalized question. In Philippines which the country I live. You can retire at piece with just 1 to 2 Bitcoin considering you complete the payment for your pension to have a monthly source of passive income aside from your investment. Food and accommodation here is very cheap.

But this will not work on country like US or EU since cost of living there is too high for 1 Bitcoin to last even a year without any other source of income.