At what point in history did physical competence stop being the most important thing that determines one’s life?

I’d say it started to become less important around the industrial revolution. Before that, physical strength and stamina were essential for survival – if you couldn’t hunt, build a shelter or fight off attackers, you weren’t going to make it very far. But as machines and technology began to take over more of the manual labor, physical competence became less of a factor in determining one’s success. It’s like when a factory replaces all its workers with robots – suddenly no one needs to be physically strong to do the job anymore.