I think this is purely a cultural background issue. People with systems/sysadmin etc. background have been mentored and thus grew up to use vi (it is available

I think this is purely a cultural background issue. People with systems/sysadmin etc. background have been mentored and thus grew up to use vi (it is available from any unix terminal prompt and is not an OS in itself™). People who grew up in comp/sci/phy used to see emacs as their first editor, and used it mostly graphically. I think switching is done either as a switch given because of the evolution of one's functional role -- be it involuntary or voluntary (latter just for fun or self improvement).