It was 8-core chiplets last generation, too. It's now 8 core CCXs instead of 4 core CCXs, but same total number of cores per chiplet as last gen it was 2 CCXs per chiplet and this gen it's 1 CCX per chiplet.
You can see it's the same overall amount of "stuff" in the chiplet. It went from 8c / 32MB L3 per chiplet to... 8c / 32MB L3 per chiplet. But it's now not divided into 2 smaller chunks as it was.
This image shows the change more clearly: https://images.anandtech.com/doci/16214/Zen3_arch_19.jpg
You can see it's the same overall amount of "stuff" in the chiplet. It went from 8c / 32MB L3 per chiplet to... 8c / 32MB L3 per chiplet. But it's now not divided into 2 smaller chunks as it was.