The generalisation of this concept is what I like call the "kilobyte" rule.

A typical web page of text on a screen is about a kilobyte. Sure, you can pack more in with fine print, and obviously additional data is required to represent the styling, but the actual text is about 1 kb.

If you've sent 20 MB, then that is 20,000x more data than what was displayed on the screen.

Worse still, an uncompressed 4K still image is only 23.7 megabytes. At some point you might be better off doing "server side rendering" with a GPU instead of sending more JavaScript!