I finally get the concept of falling rate of profit!

There was a little aha moment when reading Kali Akuno et al, specifically this part:

Marx demonstrated that as capitalist production develops and advances, competition and the need to secure greater productivity from workers drives the adoption of more productive, labor-saving technology and techniques that replace workers with machines. When labor-saving techniques are introduced, more of each dollar of capital expended in production is invested in machinery and other tools of production, while less is used to hire workers. But the increase in productivity does not cause new value to be created. According to Marx it is workers’ living labor that adds all value to commodities (whether goods or services), and the exchange value of a commodity in the marketplace is determined by the socially necessary (average) labor time required to produce it. Every average hour of labor required to produce a specific commodity yields the same amount of value, independent of any variations in productivity from technological advances.

Since technological innovation decreases the socially necessary (average) labor time required, it decreases the value of the commodity. The same amount of value is spread out among more items, so the increase in productivity causes the values of individual items to decline. As things can be produced more cheaply, and because they can be produced more cheaply, their prices tend to fall. Due to competition, companies must lower their prices when production costs decline. If they don’t, they risk a significant loss of market share or even bankruptcy when competitors cut their prices in response to reduced production costs. As a result, the amount of surplus value (profit) created per dollar of capital invested, the rate of profit, necessarily falls as well. The reality is that productivity increases under capitalism produce a tendency for the general rate of profit to fall.

Since the 1960s and more intensely since the 1990’s, we have witnessed capital’s steady incorporation of automation, computerization, and digitization into the commodities production process. The mass introduction of containerization, computer numeric control (CNC) production, and digitization have displaced millions of workers from the global labor market. And with the introduction of the internet and cell phone technology, etc., there are hardly any people left on Earth who aren’t being directly impacted by this rapid technological change

But capital’s ability to reproduce itself and expand, depends on the accumulation of surplus value, a portion of which must be reinvested in means of production and labor. In more stable periods of capital accumulation, the crisis of realizing profits which is endemic to capitalism is moderated. But the general tendency of decline in the rate of profit, or accumulation of surplus value, forces efforts to bridge the gap between needed and actual rate of profit through extreme measures. Some of the extreme measures capital employs to reproduce itself include the deployment of vicious social control strategies like neoliberalism, which call for austerity and the privatization of social goods, or fascism which calls for political terror. Both of these strategies are designed to discipline labor and make it more compliant, drive down wages, and enable the plunder of natural resources more intensely and efficiently in order to restore profitability.

and even more specifically, the part where he wrote "Since technological innovation decreases the socially necessary (average) labor time required, it decreases the value of the commodity. The same amount of value is spread out among more items, so the increase in productivity causes the values of individual items to decline."

Amazing! It feels good when it a concept clicks.

The part I was missing was the direct and non-negotiable link between labor and value, which I suppose is pretty important concept in Marxism.