question is, wouldn't you still be better off getting the canon R to be able to use native glass and lenses like the 28-70 f2. Are those lenses possible on the sony mount? Canon glass always seems better than the competition and as everyone in any photography forum points out glass matters much more than the camera body.
Also as a landscape photographer the variable neutral density filter would encourage me to shoot with EF lenses and that adapter for some time. Besides this camera seems like a slight upgrade to the 5D at a price around or less than what the 5D sells for used.
Canon could have done more, and probably should have but they seem to rely on selling their system through their lenses rather than camera specs https://appsync.biz/solitaire/ Mobdro AnyDesk