The PRO Threadrippers are not cut down, they have 8 memory channels and 128 PCIE 4.0 lanes. I think the only limitation compared to Epyc is that you can have 1 socket only.
And WRX80 has dedicated chipset lanes (https://www.amd.com/en/chipsets/wrx80), so effectively more PCI-e than EPYC, and bootable NVME RAID support on top.