If your workload is primarily I/O then coroutines will lose on the wall clock. And of course parallel workloads are fiddly.

But it's also worth noting Golang's current implementation of channels and messages is (as I've noted) going to be notably slow. Odds are you are going to avoid channels entirely if you care about maximizing multi-core performance.

Which is not to say that Golang "isn't fast". Just that it's not at all surprising that for some workloads NodeJS would outperform it.