Health and safety laws, when reasonable, serve a useful social function, preventing exploitative inhumane practices.  Child labor laws in some cases may prevent exploitative and inhumane practices, but often serve to prevent young people from having opportunities to escape poverty.  Poverty is often fatal.  Minimum wage laws mostly just cause jobs to get outsourced, or left undone, and reduce growth while increasing unemployment.  Collective bargaining is a much more efficient way to raise the market value of labor, in the long run, albeit not without its complications and struggles. 

Rather than comparing obsolete historical circumstances, you should be comparing modern jurisdictions with different labor standards but similar economies.  If we stop using printing presses due to the advent of computers, does that mean we are condemning ourselves to Black Plague? That something is a modern practice does not mean other aspects of modern life are crucially dependent on that practice.