It depends how much that rumored turbo-boost can sustain, and what is the base freq.
Remember, Cell was a monstrous (for its time) SIMD machine, which ran at 3.2 GHz without throttling. If we assume sony have a high-quality binary translator for Cell on the Zen (i.e. not some stupid interpreter emulaton), then those cores have to sustain the same throughput as Cell, and that's quite a bit for some operations. For instance, a Cell SPE could do matmul at 25Gflops, and Cell had 7 of those available (one to the os, the rest -- to the app). Now, Zen2 has 256-bit wide SIMD (vs 128-bit on the SPE), but for the binary translation to put two SPE threads on a single Zen2 core, that can be quite an engineering challenge.