I agree that Olympus is expensive, and that's why Canon EF-S is attractive.I fail to see that. Yes there are many mFT. More than half of them have no AF, so to me of no interest at all. And all mFT lenses come with 1 stop disadvantage vs. EF-M. Equivalent (1 stop faster) mFT lenses are typically larger and far more expensive than EF-M.
Just some examples:
EF-M 22/2.0 is equivalent to mFt 17/1.4, which is not available. Even the Oly 17/1.8 is twice as expensive as the EF-M 22/2.0. Not even to mention the Oly 17/1.2 which is a mind-boggling 1400 € for a quarter-sensor crop lens
EF-M 28/3.5 IS STM Macro -> mFT Pana Leica 45/2.8 Macro at € 600+
EF-M 32/1.4 -> mFT Oly 25/1.2 costs way north of a grand ... plus mind-boggling size/weight for a quarter-sensor crop lens
I really fail to see I see why anybody starting out today would chose mFT over Canon EOS M/ EF-M system.
But the discussion is about the future, long term viability of the two mounts, when all is mirror-less, and dSLRs are gone.
I think we all agree that in the future all EF lenses will eventually be RF lenses.
But with EOS-M you can't do the same as with EF/EF-S, because the mounts are not compatible. Thus, when a buyer has to choose a small system, he can look at EOS-M, Olympus, Pana, Fuji, etc., nothing ties him to Canon, because there is no upgrade path due to the RF/M mount incompatibility. At present the EOS-M lens line-up has less choices than other systems, though in the future EOS-M has to compete against the others. (After all, Canon most likely released the EOS-M system to compete with m4/3 etc.). Nowadays you still can adapt EF/EF-S lenses, so you still have a wide lens choice. But in the future EF/EF-S will be obsolete.
So, what is Canon to do?
Yes, they can increase the EOS-M lens line-up. But to maintain two complete lens line-ups (RF and M) does not make sense. With EF and EF-S Canon can make a choice only to produce EF-S lenses specially suitable for crop bodies, the rest is covered with EF lenses, so crop body owners have an even larger lens selection than FF owners.
With EOS-M expanding your system with RF is not possible. So, to compete with full fledged systems a la m4/3,Canon would have to offer a lot more EOS-M lenses (I am not considering manual focus lenses), for example, an EOS-M 100-400 to compete with an Olympus 100-400. (Here we ignore the price issue, but I think Panasonic would be a cheaper m4/3 competition - all the arcane f-stop discussion, most customers don't care about that, as long as you get the right focal lengths for the right price/size/weight. And if you want portrait, you buy your f1.4 or whatever lens, and don't care if system zy has 1 stop better DOF than system xzy because of sensor differences, if you care for such things you most likely buy a FF system anyway). When buying a new system people do consider the possibilities and options they have for expansion even though they might never buy an extra lens. But as mentioned, expanding the EOS-M lens line-up means producing two different lens line-ups, for RF and M, the size of the M-lens line-up determining its competitiveness.
So, should Canon struggle to maintain two lens line-ups, or ditch M and make compact RF crop bodies?
The RF lens communication protocol is new and the most future proof, EF/EF-S, and M is old.
Thus, it is not an unlikely scenario that at some distant future point, M will be retired, and all with the RF/RF-S.
If EOS-M stays more or less as it is, with no RF upgrade path, to me it is not an attractive system anymore, as I explained in previous posts,
and Canon would loose me as customer. But as mentioned, at present I am still very happy with my Canon crop body and EF-S and EF lenses.