In addition to what others said, home-etched PCBs are just much lower quality. We're no longer living in a world where every component has leads on a 2.54 mm grid, so tolerances matter a lot more. Also, SMD means you really need vias and a solder mask.

The problem isn't that people outsource it, it's that they need to outsource to China. That's an abject failure of domestic PCB manufacturers who simply don't want to deal with retail customers.