Apple TV 4k has an idle power draw of 0.49W and a 4k streaming power draw of 2.31W. That mini desktop will likely run at around 20W idle and approaches 30W under relatively light load and up to 60W on high loads. Plus keyboard and mouse are generally terrible couch devices. I've already got a NAS and plenty of devices I can stream from. The Apple TV is an almost perfect small and efficient device to stream to.