A clear, obvious, giant checkbox to absolutely and unequivocally disable comments.
Many if not most WordPress sites are not blogs and don't contain blogs and ALL of them get automatically spammed as soon as they are up and running.
With all the options and checkboxes in the Discussion tab there is no single Disable Comments to be able to just turn off the thing completely. There are various settings that sort of help reduce it, the closest is "Allow people to post comments on new articles " but even that one doesn't seem to prevent new spam and comments from coming in. Despite even having no posts on the site.