I don't know about others, but I was part of that spike and I went . . . far away from Common Lisp.
Learning Lisp absolutely blew my mind. I felt like every page of Peter Siebel's Practical Common Lisp was some new kind of glorious revelation. I was going to write everything in Common Lisp.
I did write some fairly serious things in CL, but in the end, it came down to what felt like a broken, barely documented, half-assed ecosystem for doing most of the things that ordinary working programmers want to do.
I realize that sounds harsh and unfair (though I'm hardly the first person to put it in those terms), but the problem is relative. It's not a total disaster as such, but if you're used to the ecosystems of languages like Java, Python, Ruby, PHP, Javascript -- almost anything else (including, in recent years, Haskell) -- you'll probably find yourself frustrated with CL. I did, anyway.
So what did I do? I abandoned CL and took my knowledge over to languages like JavaScript (cum Underscore) and Clojure.
The OP ends that quote above by asking "What can we learn from that?" I don't know. I don't know how a group of brilliant programmers working in one of the most brilliant languages of all time end up turning enthusiastic newbs into people who feel frustrated and disappointed. But I'll say it: It for damn sure ain't the language or the skills of the people who work with it.