Not surprising, of course, given that both are (originally) document-layout systems first and foremost, and given that we write horizontal lines, the primary la

Not surprising, of course, given that both are (originally) document-layout systems first and foremost, and given that we write horizontal lines, the primary layouting constraint has always been the width of the page/monitor/clay tablet/whatever, and the text (and possible other content) then just flows to whatever "height" is required (or until one runs out of space).