I'm not about to put any money down - I lack that degree of confidence in my prognosticating - but I doubt the terminal will ever really vanish, for much the same reason that 20 years of touch screens hasn't really put in a dent in a keyboard and mouse for serious work, and game controllers have barely changed despite multiple attempts at VR and other interfaces, and why the stylus is still going strong after more than 5000 years. Sometimes you just get it right.

A text interface is just really damn good at efficient and precise information delivery and interaction, in a way that takes a lot more work for a GUI to match, and they are composable in a way GUIs simply are not. Most users won't - and currently don't - care about terminals, but I doubt it will ever stop being a standard tool for power users.

I don't doubt we'll see new paradigms emerge, but I think they'll come in the form of higher level abstractions for certain classes of task rather than a replacement for the sort of TUIs and GUIs we have today.