I find my M10 far more engaging than my mirrorless because the M10 has no AF and no IBIS to aid me. Also for street photography being able to see outside of the lens’ FOV means I can anticipate shots while still using the viewfinder.
Even if Canon made a MF APO lens who is the target market? It’s going to be much more expensive and most likely larger than the f1.8 primes despite having no AF and a similar aperture.
Also Canon like Sony and Nikon are systems that are used to get the job done which is why they all are packed with the latest technology. Leica is a prestige brand/system where people are happy to pay more for less technology but a more enjoyable experience (very subjective).
For street photography in particular the more compact bodies and much smaller lenses is where the M system really shines. Not to mention Leica’s GUI is the probably the best on the market alongside Hasselblad.
no AF is a Leica plus/no AF would be a Canon minus--sorry, but like you're trying to have your cake and eat it there :-D Are you a lawyer by any chance? :-D
no IBIS--I've never thought that as a plus. Indeed the only mistakes Canon's made since acquiring me as a major customer in 1995 was blocking third-party AF lenses on RF, and being so late to the IBIS party.
see outside of the lens’ FOV--I totally agree with this point, good point.
the more compact bodies and much smaller lenses is where the M system really shines-- meh, the R5 is not significantly bigger than my old M6. In fact if anything it's too small for my hands but after several years I've finally gotten used to it.
Leica’s GUI--I haven't looked at it but this is about the last thing I'd consider. I've only used Canon so it may be that the Canon software sucks and I'm just too used to it to see it, I admit that, but in my M6TTL days the "GUI" was frame lines that wouldn't be correct on an image that had a different point of view and since I never put batteries in the thing, nothing else :-D I actually was fine with it (and the Mamiya 7, same story).
more enjoyable experience--I did like shooting Leica a lot, which is why I tied up $10k in two lenses and two bodies, but what I didn't like was having to send equipment to Germany every time I dropped it. I think I dropped Leica gear 5 times and needed 3 repairs. I probably dropped Canon gear 200+ times and needed 2 repairs...