Now we see through a glass, darkly...
- Apr 5, 2016
Sure (although I'd caution against using your anecdotal experience as evidence, I've met fewer 7D users than you no doubt, but none of them had a FF camera as well). But that's rather beside the point - it's not an upgrade path as is commonly meant here. Cross-compatibility of lenses makes it easier to use APS-C and FF bodies at the same time, but the people who've criticised Canon (or at least been confused by the current approach) were framing it is bad because they claimed the progression from APS-C to FF was no longer there (because M lenses can't be mounted on RF bodies). I expect the number of people using both is even smaller than the number who went from exclusively one to the other, and both numbers are dwarfed by the cohort who never 'progressed' at all, hence Canon's decision to make the systems incompatible in that regard.
As I've stated several times already, I doesn't seem to me that Canon is at all concerned about providing an upgrade path from EOS M to EOS R! Not at all!
They're determined that the new entry level for all serious photographers will be a full frame R body that is as cheap as APS-C x0D bodies were 15 years ago. Already the RP is one-half the price of what a 20D cost, when adjusted for inflation, when it was introduced in 2004!
The M series of cameras and lenses has always been about non-enthusiasts who want an affordable camera and a couple of lenses that are compact and easy to carry with them when a phone is not enough for the photos they wish to take of social events or travel/holidays/vacations in their lives. The M series has never been about self-described "photographers", it has always been about "the masses" who have made it the top selling mirrorless system in the world.