If so, I am hoping it is the latter of the two theories, since that could be easier to correct for most people, especially if something as simple as a firmware/software update could fix it. My method cutting out much of the middle man (controller->receiver->desktop->game) leads me to think its one of those two theories. I think it is either the number of 'hops' the controller input has to make (controller->receiver->Link mainboard->switch->router->desktop->Steam software->game), with each adding just a little bit of latency to the journey, or its a Steam Link hardware/software issue that is adding the more noticeable portion of latency. Providing you are not saturating a 10/100 and your latency is already very low, I don't think going to a gigabit connection is going to improve controller responsiveness by much. The problem appears to be the latency/responsiveness of controller input being sent to the desktop on top of the minor display latency. I know the ethernet connection isn't being saturated and the latency itself doesn't appear to be a problem for streaming highly quality 1080p and sound, it's certainly better than my WiFi connection. It's 10/100 ethernet connected to gigabit switch which connects to a gigabit connection on my router. I was just spouting off the top of my head of what I thought I recalled and TechLarry's mention of gigabit cemented that misinformation. Granted, I still need to use the Steam controller to startup the Link, but its no big deal. That made the biggest improvement in terms of responsiveness, especially with racing and fighting games. Using a longer USB cord to connect the wireless receiver to, I was able to get a strong enough signal to use the Xbox One controller in my living room. The second thing I did, for games that need quick response time, was use the Xbox One wireless controller I have connected directly to my desktop intead of the Steam controller that is connected to the Link. I never knew it existed until a few months ago when I was searching through the Steam forums for ways to improve responsiveness. The first thing I did was enable Nvidia hardware encoding for the streaming (its an option in your Steam console). However, I did find some ways to improve the responsiveness so that majority of my games play much better on it.

I have a Steam Link (connected via gigabit LAN) and can agree to it not that out the gate it was not the best for games that require a fast response.

Steam link on samsung tv