Maybe maybe maybe 4c is chiefly a process tweak, that going lower power let them use more aggressive process scaling. Maybe. But that's still a huge die-space reduction that makes me think there's some secrets like here in this chip, that chipsandcheese.com was able to uncover with read deep prying/benchmarking.
I do wish the graphs in this article had a comparison processor or two. A regular Zen 3 would be great.