> No one thinks of software size primarily in the context of their disk space.

This is wrong. The reason why many old tools are so small was because you had far less space. If you have a 20tb harddrive you wouldn't care about whether ls took up 1kb or 2mb, on a 1gb harddrive it matters/ed much more.

Optimization takes time, I'm sure if OP wanted he could shrink the binary size by quite a lot but doing so has its costs and nowadays its rarely worth paying that since nobody even notices wether a program is 2kb or 2mb. It doesn't matter anymore in the age of 1TB bootdrives.