I a broader sense, for me, RF-S can never be a proper upgrade from the M line, it will always be more unwieldy and huge. The original M (which I still have and use) with the 22mm is what I still hold up as the ideal size and form factor for a system that you can have always with you. For an RF body to get close to that form factor, it will likely have to drop IBIS since that seems to add 5mm of depth and have a square-ish body aspect ratio to fit the RF mount while limiting the width.
Getting back to the topic, I find it hard to form an opinion on it without knowing which APS-C bodies and RF-S will follow in the next few years. With the 2 current bodies, the R7 and R10, it seems like a hasty, very low effort attempt at filling with crop UWA gap(s) in the line up. It might start making more sense if EVF-less bodies get announced and designed-from-scratch constant f/2.8 UWA zooms.
But seeing how EF-S didn't get a lot of attention from Canon and EF-M even less (but with gems like the 11-22mm, 22mm and 32mm!) I don't see how of why Canon is going to divert their sole lens design team from filling out the FF RF line to designing RF-S lenses.
I've always had the impression that the APS-C line at Canon was only there to bring in the money to work on the things they actually find interesting: FF bodies and exotic L lenses. That might change with both the APS-C mirrorfull bodies and EF-M being discontinued, but I think we'll always get disappointed by Canon when it comes to APS-C, especially when they release things like the EF-M 32mm, M6II and R7 just when I'm ready to abandon all hope