This, if you live and work in the USA. I don't know how it works in Europe or Asia, but in America, unless you have F-U Money like OP says, you are just 1 major health issue away[1] from bankruptcy if you go the "frugal" retire early i.e. retire without F-U Money.

Source: My Manager's sister, in her early 50s, who had early stage throat cancer. Despite having insurance, it quickly maxed out, and hospital stays even for 3/4 days are in 1000s of $, and not all medical events are covered at 100% even by the best insurances. She (the sister) is now using my Manager's insurance to pay for some of it, and hasn't been at her job in 8 months, so also afraid of getting laid off.