The drawbacks can be refuted quite easily:
- Nethack definitely doesn't qualify as a "cheap" game (even when it's free software). Nor do many MUDs.
- Keyboard shortcuts (or command-line parameters) aren't necessarily hard to memorize, especially when they're shared between many applications (many apps in Unix know something about Emacs keys, for example). Besides, everything in GUI can - and should - be bound to menu shortcuts anyway.
Besides, no matter what type of UI you use, you'll eventually, eventually, get used to it. =)
- People who claim that character user interfaces can't use more than one file at time obviously haven't seen Emacs. Or screen, for that matter...
(Needed some to express some good-tempered counterpoints - I didn't want this to turn into a Holy War. =)