Well, perhaps it is time for large, ethnically-homogenous countries that are on the ascent to adopt diversity policies of the sort that the US was approaching before the "vibe shift"
Canada is largely still homogeneous but still welcoming to immigrants and very close to the US. Rather than China totally changing cultures, I think it’s more likely that US-based companies will have large satellite offices in middle powers.
I don’t think diversity policies are what made America diverse.