I dont think that constitutes rejection of Marxism. If you do everything within your power to bring about communism, are you not rejecting it.
If there is more in your power to do and you choose not to, then that is rejection.
This comes back to rejection being a matter of choice.
Does a slave reject freedom, because they dont have it and cant obtain it? Is a cancer patient who cant afford treatment rejecting treatment? Of course we wouldnt say these things because rejection implies option and choice.
They live in cultures completely counter to Marxism. In practice they reject Marxism because they do not live its principles.