If your connection can maintain over 3 Mbps steadily, you should get adequate service (as good as ATSC) from modern streaming services. Back when h264 was state of the art, good 1080p streams would be at least 8Mbps. I have a dedicated fiber 50x50 connection. With all of that always available, Netflix streams to my Roku with VP9 at just over 3Mbps for excellent 1080p video. 4K tops out at a little under 10Mbps. If Roku ever comes out with a device that supports AV1, the values will fall further.