They come from the same tendency that split from MLs over Khruschev’s revisionism, and then split again over China’s revisionism as part of the collection of tendencies that turned into like Maoist Third-Worldism and whatnot. “Ultra” doesn’t necessarily mean “wrong about everything,” it’s just a catch-all for all the “too-ideologically-pure for this world, and so at odds with anyone who’s ever made a concession to material necessity before” tendencies, if maybe a bit less than leftcoms are that same thing. Like the Hoxhaist critique of China’s geopolitical strategy is cogent and accurate, if maybe a bit too harsh since there are material reasons why China has done what it’s done. The Chuang Collective are ultras and they wrote and published a detailed history and analysis of Chinese economic development and labor movements and the material conditions China was dealing with post-revolution, for all that they then bookend it with flowery denunciations of “the CCP” [sic] for not being sufficiently ideologically pure and ridiculous calls for China’s destruction to bring down the American economy.