Ok, but the 5D Mark II was a gamechanger and in my opinion creates a result that still beat the III, IV, and many cameras that came after.
But the 5D4 is superior, from the lovely focus-pulling via touchscreen to 1D-grade focusing. Let alone GPS, dual cards and the buffers.
There were definitely areas where these SLRs could improve from generation to generation, which seems to be much reduced regarding the iPhones, since the form is fixed, and upgrades or changes are often extremely unobvious.