The 5D Mk IV is capable of extremely sharp photos. Most of the time sharp photos are user error and not the camera. Cameras do what we tell them to do most of the time that is.
Lenses make the shot. Not the camera. The camera basically becomes a storage device for what the lens saw. Usually the better camera produces the better photo, however. Of course input form you as the photographer and the camera doing its thing place some parameters to this. That is where I would start my investigation as to why you are not getting super sharp photos.
Start with a full reset of the 5D Mk IV back to default settings. Set P mode, ISO 200, daylight and One shot. On a nice sunny day do some random shots, trees, fences building, etc. They should be sharp. If they are not try a different lens. If they still are not sharp call Canon for a service order.
EB
EOS 1DX and 1D Mk IV and less lenses then before!
