I don’t think so. With FF coming down in price, the need for an APS-C body to carry for an “emergency” isn’t required. Also, FF has come down in size as well. The excuse that you get longer reach with APS-C gas never made sense to me anyway. Just crop your image. Yes, the apsc tele’s are smaller, but when has a company made serious long APS-C tele glass since FF has come out? Would thy really sell enough $5,000 to $12,000 APS-C lenses? I don’t think so. What about extreme wides and zooms? I doubt it.
these companies have experimented over the decades, and it seems that the large majority of customers have said - FF. Maybe, if the cameras market hadn’t been imploding since 2012, or so, there would have been a big enough market for this. But not now. The R7 is a pretty good camera, but would Canon come out with an R5 equivalent, or an R3 equivalent? I highly doubt it. Who would buy a $3,500 to $5,500 APS-C body and equally expensive lenses? Probably not that many.