Let me say I firmly oppose Canon's decision to abandon the M mount as a consumer and from and engineering standpoint.
Now from a business standpoint, it was logical to unite everything under a single mount and consolidate R&D and give the same pathway the EF mount had, and in fact a better one for folks wanting to "upgrade". I use upgrade in quotes as I don't see FF as an upgrade, merely another option. Canon would love for you to think that way as its more margins to the bottom line for imaging division obviously.
The M system is a fantastic one. That said it has a few hiccups that will go unanswered now that we're not left wondering it's fate:
1. No more glass. No fast f/2.8 zoom. The end of that wish.
2. No more bodies, so no IBIS and no EFCS for that 90D/M6 II sensor in and M mount. Big bummer.
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Otherwise? M is a great system, still.
I quietly jumped ship a few months ago due to my keeper rate being sub-par due to AF and shutter shock. The IQ is there when it "hits" but it was annoying enough for me to pull the plug. I always suspected Canon was gonna do this (R50 and adapt more M glass to RF-S with some minor necessary compromises). In fact, I suspect Canon will adapt most of the M glass over time to RF-S. They'll have to make some compromises... 55-210 lost 1/3 stop to make room for the control ring and less optimal flange which "ate" into it on both ends, 18-45 lost the 3mm width due to the flange. 32mm ain't gonna happen, consider the FF RF 35mm f/1.8 IS STM instead. 22mm and 11-22mm may happen, but, the 22mm may be f/2.2, or just larger (probably just larger, which is fine, the mount is larger to accommodate. In fact, maybe we'll get a RF-S 22mm f/1.4. Wouldn't that be something?).
Anyhow I digress.
It's a sad moment for M. Been that way for the past, 4 years? We just only figured that out when the R7 and R10 showed up last year, but it's been suspect for some time.