Equally depressing is the thought of giving up all the ground gained and lessons learned every time a new fad takes the stage. Watching the same mistakes made over and over, only moreso... That's depressing.
I think this as much as anything contributed to my burnout. Burnout is maybe too strong a term -- disillusionment is maybe better. I see younger devs getting excited about something new, and to me it's just "yeah I've seen this movie before." The novelty factor is just gone -- work is simply not that exciting.
The thing is, though, that there are probably new technologies (or at least technologies that are new to you) that you'd probably find interesting.
The key is finding them and giving them a chance.
When I was young I hadn't heard much of Lisp, and what I did hear didn't sound that great (Lisp was old and maybe it was great back then, but technology has advanced so much, I thought, that it's probably not worth bothering about)... but when I did finally learn it I fell in love and wished I'd learned it much, much earlier.
And it wasn't just a copy of something I'd learned before, as were many other technologies that I'd learned.
That said, when you are seriously depressed or burnt out (the two go hand-in-hand), it's tough to find anything interesting, even things that you'd normally be fascinated by.