TIOBE is a terrible indicator generally. More activity doesn't mean more people are using a language. I wouldn't work for anyone using it to make decisions :)
The Cognitect website[1] lists quite a few success stories using Clojure. I would trust the names in that list far more than TIOBE.
But really what sold me on the language was the quality of the libraries, the incredibly helpful community and its shared focus on simplicity. Reading about a thing is no substitute for hands-on experience; its hard to judge the trade-offs you're making without it.
The TIOBE index [0] fwiw (please debate) suggests by going from JS to Clojure you'd be switching from the 7th most popular language to the 47th.
In that 'top 47' there are only 3 lispy langs present, 'Clojure', 'Lisp' and 'Schema'. That suggests programming in lisps is a very unpopular idea.
[0] http://www.tiobe.com/tiobe-index/