I actually can't think of a tool I use day to day that I wouldn't recognise from 20 years ago even the really good stuff would be obvious in it's intent (intellij etc).
I'm not really sure where I'd be able to improve significantly on day to day tool usage, maybe a shell that doesn't use bash as the language would be nice (I know there are other shells but bash/dash are the defaults on pretty much everything I touch I can get to a command line on).
That 'just' is worth a fee billion dollars though.
Makes you wonder if there are other tools in our world that could be a 'just' away from a billion dollars.
25 year ago isn't //that// long ago? People using IRC at that point (I guess techies) surely would recognise it fairly easy.
Similarly you could look at a brand new Tesla and recognise it from a 1st car model or even a wagon.
College students, mostly.
Hung around for about 5-6 years and it's been around in the background ever since, just got back into using it recently as one of the frameworks I use has a decent IRC channel and an even more decent offtopic, nice bunch of folks and with the ability to throw it in the background it gives a water cooler feeling when I'm working on my own and need to bounce an idea of people.
He said something that I always found interesting. He was talking about how in a decade or so we would probably be using software and tools that would be unrecognizable to us at that moment, but after a pause he added: "but we'll still be writing code with vi." :)