There is no denying the Canon EOS was not a major success. I wrote about it last June and even bought a bargain-basement version just out of interest. I tried it with Leica lenses with some success. I liked the touch screen controls and I enjoyed using it with a a 35mm optical viewfinder matched to the rather good 22mm prime lens. But it didn't last. There were no compelling reasons to pick up this camera in preference to, say, a Fuji X-E2.
Canon omitted the EOS M4 from the succession and went straight to the M5 because four is an unlucky number in Japan. Should they have considered the fate of the Leica M5?