They probably also use Outlook. That's what I do (4K employees). Used to use Mutt almost exclusively, but just became too hard and people complained about my emails turning everything to Courier. :)

I still use Mutt to quickly prune emails in the AM and for writing to mailing lists.

I've (sadly) gotten pretty used to Outlook and like it quite a bit. I do miss using vim to edit emails though...

The parent to you post was responding to this:

> In most big companies you can't really afford to do any email client shenanigans.

So... what does the percentage of employees using Mutt have to do with that?