There used to be a time where every new coder spent a couple of years learning/maintaining their elders' code - fixing bugs, porting, optimizing, learning about how the environment(s) integrated. The concept of journeyman in sw was a thing, and mgmt/team expectations from the youts was appropriately gated.

Now it's different (outside of HW orgs), but as I look out a decade or so, I'd rather have a part-time retirement job "cleaning up" interesting projects than travel/consulting.