The other factor here is that the increase in up-front development and fabrication plant costs has been absorbed by economies of scale, i.e. the semiconductor m

The other factor here is that the increase in up-front development and fabrication plant costs has been absorbed by economies of scale, i.e. the semiconductor market has grown massively in recent years, and it's debatable how much further it can grow. Without that growth there is a natural limit to how much money gets spent on each new fab plant required for each fabrication phase.