In my experience, a second nic is important to build anything with resilience; it's not just for routing. I see it as the most important hardware to "double up"

In my experience, a second nic is important to build anything with resilience; it's not just for routing. I see it as the most important hardware to "double up" on. If you are building a small cluster, for instance, you generally want to have one interface for the backend interconnect and one interface for client traffic. Or maybe you want to be able to upgrade or change your networking without taking traffic offline -- you'll need two physical connections for that, too. Of course you can still build routers and everything with a single interface (which is why I noted the single port hardware in the first place), but if you are going to design something specific to the mini-server market, the cost difference between a single port and dual port controller is negligible enough that there's no reason not to include 2 or even 4 ports. The GoWin machines simply toss in an OCP nic slot and call it a day. That would be a fantastic solution to see adopted by other vendors.