While I appreciate that Marx made a case, this is not data or evidence. It seems intuitively true, but that doesn’t really move you closer to real proof.
What would count as real proof, if not prices falling due to competition?
I’m not sure if you are trying to imply automation is a good or bad thing. Looking through history, the industrial revolution was bad for the workers of the time, but in the long run massively improved the living standards of everyone. Automation is a net good in my opinion. Competition is simply an accelerator, this is not really tied to the economic system being used. In capitalist or communist systems, firms that are protected from competition (by what ever means) do not innovate as fast or as effectively (see Intel as a great example of this).
I’m not arguing whether automation is “good or bad,” I am strictly speaking about the inherent unsustainability of Capitalism. Automation is good, but in Capitalism is used to purely benefit Capitalists, as wages stagnate with respect to ever-climbing productivity.
While this can be true, it is not necessarily true.
Why would it not be true? This still doesn’t explain why you stated Communism to have a poor track record, no AES state has yet made it to Communism, as Communism must be achieved globally.
As your population ages, the costs to care for them raise at an increasing rate. If you don’t have enough new workers to stabilize the economic base, the burden that an aging population places on the younger generation grows until it becomes untenable.
Again, this has nothing to do with Socialism or Communism. It seems to be referring to welfare for elderly people, which exists in all systems.