>You have to be critical in the right way

But as to what this "right way" is has been at the center of the defence of critical theory, see for instance the positivism disputes and the accusations of reductionism from both sides. To say that Marx wasn't critical of inadequate explanations is false, since again his whole project was to criticize the ad-hoc solutions of the political economists (such as their use of the labour theory of value in which some goods were conveniently fixed in value to explain how wages for the same work can vary). You might think that Marx's reflections on his own explanations are more lackluster, but at least he claimed to be accepting criticism[0] and to say his own explanations were wrong is different from saying that his mode of explanation is wrong. Marx claimed that his results had more explanatory power than those previous theories. To say that Freud wasn't critical is similarly inaccurate, since before Freud the explanations offered were poor (especially when one considers that Freud practically founded the discipline of the study of the mind). It's a little known fact that the same standard Popper attached to Freud's theories, of a "metaphysical research programme" he also attached to Darwin's. Even if it isn't science, the claim that it is unfalsifiable has met considerable resistance[2].

>That's not a dogma, that's the definition of science.

As the article points out there have been many definitions of science and ways of going about it; consider, for example, the German philosophers who contended that science was rigorous and systematic study. To say that a particular (Popperian) vision of science ought to claim authority over science is ironically a claim lacking in much explanation itself. In any respect, the dogmatism is when scientists use a method which has faced sustained criticism from philosophers of science without paying heed to the criticisms. The issue actually seems to be political[1].

[0] "Every opinion based on scientific criticism I welcome. As to prejudices of so-called public opinion, to which I have never made concessions, now as aforetime the maxim of the great Florentine is mine: Segui il tuo corso, e lascia dir le genti."

[1] https://www.jstor.org/stable/4224749?seq=1#page_scan_tab_con...

[2] "Popper’s charge about the unfalsifiability of key Freudian claims is anyhow highly questionable. He himself focused on Freud’s claim that all dreams are wish-fulfillments, arguing that one can always find grounds for maintaining such a claim but one cannot specify what evidence would falsify it. This is incorrect, as I have argued at greater length elsewhere (Michael 2015). There are numerous logically possible observation statements that would falsify Freud’s wish-fulfillment claim (at least, if one accepts certain background theories, as Popper’s theory requires). For example, if it were found that the limbic system and associated neural structures essentially involved in motivation were (even relatively) inactive in the dreaming brain, that would falsify Freud’s wish-fulfillment claim in the sense required by Popper’s theory. Similarly, if it were found that no or few young children (ages 2–4) had straightforwardly wish-fulfilling dreams, that would falsify Freud’s claim in Popper’s sense." https://link.springer.com/article/10.1007/s11406-018-0020-8#...