min-width tends to be favored over
min-height in CSS because of the way that web pages scroll. Web pages typically have a single scroll bar that scrolls the page up and down vertically. Having two scrolling directions is usually bad for usability. Having only horizontal scrolling is technically difficult.
- Text works better with vertical scrolling because lines are read from right to left. Long lines of text with horizontal scrolling requires scrolling back and forth between the end of one line and the beginning of the next.
- HTML blocks by default are
100% width and expand in height to fit their contents.
- Computer mice typically have only vertical scroll wheels. That makes horizontal scrolling less convenient for desktop users.
You could conceivably produce web page that scrolls horizontally but not vertically for some limited use cases. I can imagine a layout of images side by side could work very nicely.
To get text to work nicely horizontally, you would need to use a column layout like a newspaper where text from the bottom of one column wrapped dynamically into the top of the next column depending on the height of the screen. The number of columns would be dependent on the amount of text. I don't think such a beast exists in HTML. The CSS columns layout makes you specify the number of columns up front. See this question on Stack Overflow: HTML5 CSS Horizontally Scrolling multiple dynamic number of columns
You can even find a few examples of horizontal scrolling web pages. This site appears to give awards for well designed ones. However, I spot checked several of them and only found a few of them still work well scrolling horizontally. Several seem to have changed their design to a standard vertical scroll. Others ask me to rotate my device (a portrait monitor!) to be able to use the page. Clearly designing horizontally scrolling web pages is technically challenging, even for award winning web designers.