Bloomberg found the same thing when they tried to redesign their terminals for traders - existing users were so invested in their knowledge of the "incantations" of the old interface that they were hugely resistant to a UI with a more modern learning curve and interaction.
It's very hard to make a product that essentially devalues things that your customers spent a lot of time learning. You're probably better off ignoring people who already happy with their shell experience, and going after people who have not yet invested in learning all that crap.
And yes, it's crap. And I say that not because I don't know it myself, but because in the end, much of it is not essential to the actual job we're trying to get done, it's the tools we use. And the tools are not the job.