Not saying anything is anyone's fault. With more sophisticated technical selections comes the requirement to properly select which is best for your application and learn to use it properly ... including practicing shifting the AF point around the viewfinder to avoid off-axis focus recompose errors which vividly show up with fast aperture longer lenses when used at max aperture.
These cameras aren't made for a single application, or it would narrow down the potential of who would buy them. There are a number of things I automatically set on my wedding cameras based specifically on how I use them. I don't change them unless what I'm doing with them changes. I almost never use Program settings nor AF defaults which tend to use adjacent AF points to assist ... okay for smaller max aperture lenses usually that have some wiggle room from DOF, but not so with fast max apertures I tend to shoot with moving subjects where an adjacent AF assist may grab a higher contrast point behind the subject. Even with single point AF you do learn what to focus on and where the potential for miss focus may be. Really no different than if you were manually focusing using focus assist.