Except web browsing, which is a huge part of software engineering, and which is nearly impossible to do without the mouse because most websites cannot be reasonably navigated with shortcuts alone.
So the whole model falls apart, really.
Most of my operations on a web browser involve scrolling or swapping pages, which I typically do with a keyboard. Besides every browser has keyboard extensions that allow one to select links through keyboard press. Being a neovim user I like vimium on firefox. I also like to use text based browsers for a better browsing experience and less distraction when I am coding.
Not that I know everything, but I view informational browsing as a distraction while programming. The LSP augments most of the knowledge gaps for me.
If vim isn't for you that's cool. But I find other editors for me are this-is-fine.gif.
Really, the model doesn't fall apart. But you don't have to use it if you don't want to.