Record companies create the content that radio stations broadcast, currently, the record companies create stereo mixes to send to the radio stations, these same record companies could instead send "stereo" mixes that are actually SQ matrix encoded quad downmixes of Atmos immersive mixes.
So now you say they "could instead send." "Could" is different from "would." So you think they'd just do this without telling anyone?
Keep in mind that a lot of radio stations don't get their music from the record labels.