It's the same chip as Summit Ridge.
Naples is four chips on on package. Each one is an 8-core Zen, with 2 memory channels and 32 PCIe lanes. That's how they get 8 memory channels and 128 PCIe lanes, using NUMA.
Desktop Zen has 20 PCIe lanes visible because that's all your average motherboard needs, WITHOUT BEING TOO EXPENSIVE TO ALSO HANDLE 8-LANE Bristol Ridge, and not having to switch to LGA to bring-up pin density.
But you can be sure those extra 12 leads are there on the die, just not connected to anything
Seriously, why would they do a separate core revision just to add more PCIe lanes, when NOT CONNECTING EXCESS I/O IN THE PACKAGE is one of the easiest things you can do with an existing CPU?
Of course desktop Ryzen are just dies don't used for server. A minor note, those 128 PCIe lanes are only available on single-socket platform. Dual socket Naples reduces available PCIe lanes to 64.