Before Windows / GUIs, everything was a TUI. Some of those applications were kept around for a long time even when Windows was mainstream, because they were faster. If you've ever seen an employee (or co-worker) work in one of those applications you'll see it. They can zip through screens much quicker than someone doing point and click work.

It's truly an amazing sight, our payroll system was all text based screens. I had a question and the clerk ripped through like 10 screens to get the information I needed, we're talking 200ms human reaction speed through each screen.

I also worked with a mythical 10x developer and he knew all the Visual Studio keyboard shortcuts. It was just like watching that payroll clerk (well, almost, we had under-specced machines and Visual Studio got very slow and bloated post v2008), I don't think I ever saw him touch the mouse.