Yes, we should absolutely respect the settings in the "typography" preference pane that all browsers have, where all users lovingly set their preferred text spacing, indentation, and justification. Oh wait! There isn't one. In fact, most users not only haven't explicitly made these choices, they can't explicitly make these choices. Are you arguing that the "system's choices" are some bastion of well-considered design sensibility that we violate at our peril? Really? Nuts to that.