https://news.ycombinator.com/item?id=30802479 touched on it, though I would add that the immutability is a stark departure from previous Lisps. I still think of it as a Lisp, but on an island, similar to Scheme though even more different from mainline Lisp.
I've seen people report lack of deeply capable repl, slime a few times. People don't like immutable first too (maybe they prefer metaobject update protocols).