In ATSC 1.0 I don't think this was true, at least in my area. The reason is there was a fairly finite amount of bandwidth available (made worse by sub-channels)

In ATSC 1.0 I don't think this was true, at least in my area. The reason is there was a fairly finite amount of bandwidth available (made worse by sub-channels) and they were limited to MPEG-2, so I often observed macro blocking and other artifacts. It was decent, and probably better than streaming was when it launched, but now that 4K streaming is routine (with HEVC) it looks considerably better. I'm sure ATSC 3.0 changes this.