Depending on the kind of content and the way you present it you can show a certain amount of information.
For text there is a certain limit in the width of the container depending on the font size. So there you have a first constraint. However you could still fill up the screen with more blocks of information. There are certain breakpoints, we should adapt the layout to those and use one of them (instead of a random number) if the amount of information on a single screen is reaching a limit.
For example, (these images are meant to be seen full screen) in the case of text:
ok amount of text information:
or in the case of images/video, the same amount of information: