These correlations do hold for technical fields, but logically there should be a point beyond which productivity gains outpace, demand growth / demand could even stop growing. One should either retool to solve a newer problem before this point is reached, or hope that the point is not reached in the span of their career.

Oil rig builders for example - manufacturing has been increasingly automated, but the demand for oil rig building has grown consistently. But they should probably look into solving other problems given that demand is shifting.