It's not at all about disk space (I could care less about that), it's about navigating the cursor (or point) quickly in most editors. And everyone here is using an editor that supports or can support tab as 8 columns.
Is it the case that most editors come set to interpret tabs as 8 characters?If not, one would need to communicate that to them. I'm not sure if it's still the case, but the editor I use (a commercial Emacs variant) used to ship with physical tabs and the indent size set to 4 characters. (It was the first thing I'd change, along with setting it to expand tabs to spaces to deal with the same issues in others' editors.)
