> does anyone seriously think that a Chinese global hegemony would be better
False equivalency; no one is arguing that. However, a multi-polar world is appealing. The US is certainly not always a good actor here either: the US has 50+ years of foreign interventions to point to that span the globe, particularly the middle east, latin america, and southeast asia. Less extreme: its ability to unilaterally cause pain for even allies (EU, Canada) through trade tariffs wasn't exactly welcomed.
It would be in Europe (and other regions') interest to be able to defend their own interests on equal footing with the US. Currently, they cannot do that (military and economic dependence). Having China offers leverage. I.e., the US will be incentivized to behave better if other countries can say "well if you push us too far, we'll work with China."
This is just my armchair analysis. I'm not invested enough to back this up with citations or anything so if that's what you're looking for feel free to ignore and argue with someone else who cares more.