In a company of nearly any size, consistency has many benefits, particularly when it comes to support.
Where did I write that linux was for the computer illiterate?
Such as people that have to call in because they can't find an option in outlook. Because they never bothered to look.
Those people probably need a television experience on the computer, where things are dictated to them. There are several different systems that provide that.
When did I ever imply that I was talking about "computer illiterate" people? As far as I'm concerned, if you use a computer for your job, you'd better consider yourself at least somewhat computer illiterate. One of my pet peeves is people who work with computers all day who say, "Don't ask me--I'm computer illiterate!" To me, that's like a carpenter saying, "Don't ask me--I'm hammer illiterate!"
I'm not sure why you find this unusual. Many, if not most, companies need a computer that is flexible AND consistent. They need to be able to install and customize their own software and systems. But that's where the customization ends--at the company or workgroup level, not the end user (to any significant extent). Again, it seems like you're approaching this from an end-user perspective--it's the company that needs the flexibility, not a "television experience," and it is beneficial for them to provide a familiar, consistent UI for their employees. Furthermore, very few people these days work at one company for life, so having consistent UI across many different industries is a huge training plus for all companies training new employees.