There's no inherent reason why an abundance of labor would cause wages to not track productivity (either within a sector, or across an entire economy).

In a culture that viewed the economy as a tool to enhance the living standards and quality for all of its members, there might be a very weak or even non-existent connection between labor availability and wages. Productivity gains could be viewed as way to either (a) reduce the amount of labor required (b) increase the amount of goods & services available, or both. Wages could remain fixed, or increase in such a scenario.

This is nothing like the economic system in which we live, however; an economic system that is viewed as a playground in which which some will accumulate vast resources (and thus power) and others will not can never function the way I just described.