Since you mention it, Einstein effectively retired when he escaped Germany in 1933. He was 54 years old. He found a plum job at Princeton, where he worked on what he liked, lectured if he wanted to... and if not, not. He was both retired, and not. Famously, he dismissed money as some pointless quest signifying nothing, a distraction from more fundamental passions. He didn't own his own house, or even a car. And yet, he was consummately taken care-of. I don't think that he ever worried about safe withdrawal rate, a bond-tent, the Red Zone, RMDs, tax-torpedoes, or health insurance. He wafted along, in quasi-work and quasi-leisure, until his death. Nice, isn't it? But it helps to be Einstein. Most of the rest of us, have to choose A or B... "A" being work-work-work in the conventional sense, "B" being full-time golf....Contributions of most folks on this earth, whether Albert Einstein, Alexander the great and such, can be and will be rendered moot by universe in time-equivalent of human travel of few light years.
But imagine if Einstein remained at the Swiss patent office, in his spare time practicing violin, instead of doing physics. He'd have been a lifelong civil servant, with (one hopes) cushy pension and a drama-free life in Switzerland, while Germany and the rest of the world burning around him. Serene, but insignificant. Would Mankind, have been better off? What would this alternative-Einstein be thinking, in his 70s, looking back on his life, and wondering what-if?