I recently did a quick check of the stats window in YouTube TV on Roku. Curiously the NBCUniversal properties such as NBC Sports, Olympic Channel, and my local NBC (all of which were streaming the Olympics) are 1080p30. Other 1080p30 include Time Warner/Turner properties such as CNN, and CBS Sports and my local CBS.
On the other hand, the Disney and Fox properties (such as all the ESPN and Fox Sports channels as well as my local ABC and Fox) are 720p60.
Is this an optimal breakdown? I wonder if they’ll get to 1080p60 for everything, or jump to 4K/30...
When OTA TV converted to the ATSC standard, they had two options for HD broadcast resolution: 1080i and 720p. 1080p was never considered for broadcast TV in North America at the time because it would have had to have been 30 fps, instead of 60. ABC and Fox both opted for 720p60, claiming the progressive image was better for sports. Almost all of the others went with 1080i for the higher resolution. I believe PBS might also have gone with 720p. Remember that Disney now owns ABC, so that could be why they are 720p as well.