I work at a TV station (not in Detroit) and I can say that most stations are going to settle into the middle data rate area because some stations (like mine) suffer from being in the VHF band. If we can lower the modulation and get better reception indoors then we probably will do that instead of going with a higher data rate which is harder to get. Also, I will bet that most stations never broadcast in 4k because 4k doesn't pay the bills. Having every sub-channel in HD actually does. For those that don't know, local stations gets paid for carrying sub-channels, for airing them in HD (instead of SD), and for putting them in a higher position. For example, a dot 2 will pay more than a dot 7.
Also, after the last software update I can now get the mobile version of WMYD (120.99) with audio and video. Before the last round of updates I could never get the audio on any of the channels.
ATSC 3.0 Forum
I saw the 120.99 WMYD mobile channel was added recently - what exactly is that for? It seems like a lower bitrate version that is presumably easier for mobile devices to receive, so that’s what I suspect - though do any mobile ATSC 3.0 devices actually exist?