The main point of useful idiocy here is that he is correct that these two frameworks contradict and doesn't have the guile to mask how absurd his side is.

Revolutionary movements require revolutionary theory. I don't think your argument is exactly tailism, but it functionally has a similar problem, because if you are goal-oriented then you should want to have and promote a framework oriented toward achieving those goals and, as I explained above, his framework will frequently contradict those goals, so his framework should be opposed by socialists. Can you not see how "we should follow these arbitrary commandments because I say that God said so" being treated as equivalent to dialectical materialism in terms of legitimacy is probably not good for a communist movement?

Your argument reminds me of what dem-aligned people say about only caring about results but then sacrificing everything that is the basis for achieving those alleged results because they mistakenly think (or lie and pretend) that it'll make reactionaries into helpful allies. Obviously I think you are being honest, but you've fallen for the same trap some of the supporters of those politicians have.