What they actually said was that there would be no R mount on a M body. Some people then started extrapolating that because M is APS-C that meant no APS-C with R. Go read the interview.what makes no sense is that in an interview when asked if there would be an APS-C body with the R mount canon THEMSELVES said no. So what is going on either at canon or with the "sources"
If Canon stuck an APS-C sensor in the R body I would buy one of each today. They would be completely different tools. But until I know for sure what the plan is for APS-C with an R mount I won't be buying ether. Canon sold a mountain of Rebels, Kiss, crop EOS etc cameras. Far more than they sold full frame cameras. Every one that bought one sized their lenses for for an APS-C sensor. To tell all those customers to throw all their equipment in the garbage and start over would be suicide. I would switch brands or quit photography before I would drop $20,000 -$30,000 to recreate my APS-C rig in FF.
An APS-C sensor with an R mount would not mean the end of FF cameras or the M system like some people seem to believe. A FF EOS R with a crop lens is around 11MP so can we please stop regurgitating that over and over again as the solution. It isn't.