>>2236775ofc they are not mutually exclusive. however, 'technological progress' i.e. using a compact harvester instead of a scythe (just an example of the top of my head) to increase productivity is easy to grasp and quite obviously what neoclassical economics focuses on.
LTV, social necessary labor time, those are more abstract concepts which you will not be taught in economics classes in school or university.
thus i deem those, LTV and socially necessary labor time, the 'bottle neck' to understand the tendency of the rate of profit to fall.
besides that, anyone who took an undergrad calculus class should easily be able to grasp this stuff.
which is, imho, one of the problems with (modern day) selfproclaimed marxists: they lack the mathematical education to actually understand marxist economics.