Means higher throughput with lower jitter, that in our case was what we were looking at that time. For go defense we were using PooledByteBufAllocator for recycle Output Streams but memory usage was not a concern in benchmark as much as GC does not affect throughput. But I also believe that go http stdlib memory usage is better than netty, sorry for not being more helpful with this topic.
We have both java8 and go, high throughput critical microservices with excellent 99pctl, and in general memory is not a concern (as much as we do fine tuning on gc and don't have any memory leak) and generally for the really critical and portable solutions we choose java over go (unit testing and library versatility is a big player in this discussion)