Which entirely ignores all the systemic issues that make it easy for, say, a boy growing up in a middle class household to learn programming but make it very difficult for the boy in a poor household. Or how it's not just skills that are important to getting 'above' gig work but credentials as well. We are not free agents, wading through a thin meritocracy, we are agents anchored by our circumstances, trying to swim through mud.
I'm not even thinking about poor vs. rich kids, or kids living in a ghetto vs. kids living in the suburbs. What about the man who gets laid off from work and has a family to support? When exactly is he supposed to pick up new skills, if nobody's hiring for his current ones in the area?
I got laid off last week, and I've been thanking my lucky stars that I'm a software engineer; I'm actively talking to three friends about going to work for their current employers, and I've got recruiters rattling off lists of companies looking to hire me - plus I get a severance, and my wife makes enough money that we have some bit of runway before I start having to sell clothes to feed our child.
If I were, I don't know, working at a coal mine that closed down? Or at a Toys'R'Us that got shuttered? Can't exactly hop back into a college curriculum for three years, kids don't eat lectures.
Software engineers have it pretty easy in terms of low costs for skill acquisition, but in many other areas it's just not going to be something you can do yourself. If you want to become a machinist, you're going to have to have access to a machine shop. Not impossible, but a higher bar than acquiring a computer to learn how to program. So society has to end up participating in mapping together skills acquisition and the various resources needed to actually acquire the skill.