Family number in every Zen3 processor is Family 17h or Family 18h(Zen2(18h 10h-1Fh)/Zen3(18h 20h-2Fh) pre-Dhyana semi-custom). The Zen3 architecture in architecture 18h and 20h-2Fh is just an improved Zen2 architecture 18h 10h-1Fh. There isn't any from scratch push for Zen3, it has all been pulled to Zen4. The IPC improvement so far is set to be ~12% from Zen2. With no improvement in high TDP CCDs, but significant improvement in low TDP CCDs.
2 CCDs at 115W => no improvement, no reason for Zen3(purely architecture... which only goes up to the L2 cache)
8 CCDs at 220W => significant improvement.
TSMC's N5-HPC is built for High TDP, w/ better metal vias, better CPP control, yadda yadda from N7.