I'm glad the Canon designers are having fun, but I wonder about the size and weight of such a lens. I'm a Canon M5 user, but if I were to go to full frame mirrorless I think right now Nikon is much more appealing. Practical lenses, and a Fuji style lens roadmap. In comparison, Canon seems to be sort of in left field, with large heavy expensive show-off lenses, no lens roadmap, and strange-for-strange-sake controls on the EOS R body. I had a Fuji system plus a Canon EF system, but recently sold all that and am just using the M5 at the moment. So I could choose either the EOS R or Z6 without wanting the adapters for legacy lenses. Buying into the respective new systems, the Z6 plus 24-70 kit lens is $800 less (!?) than the EOS R with 24-105 kit lens. I don't get that at all. Plus, personally, I would want the smaller lighter Nikon setup.
Just got the new 32mm f/1.4 EF-M lens. Sticking with the M5 for now, until full frame things settle down.