Letting them cheat the globalist system (e.g. violating IP laws, human rights violations, Uyghur/Tibetan genocide) may have been fine when they were desperately poor, but there was always an implicit assumption that they would eventually start playing by the rules and culturally liberalize. But they're not. How can we hold onto ideals like "diversity is our strength" and open borders are good when China is kicking ass and threatening the balance of power as an insular ethnostate with one of the lowest rates of immigrants on the planet?
And now they're growing to a power level that threatens to rival the US and its authority to police this global system we've created. That isn't stable, and the west would be insane to not shut China out and take a step back from our open, globalist ideals until we sort out this geopolitical game of thrones.