Yeah, Jarc doesn't use that version of list either. No need.
But copylist is also used by copy which is used by sort. So the sort benchmark ran into it. I guess since Rainbow compiles to CPS the copylist doesn't stack overflow in Rainbow.
rainbow grows its stack as needed, and will eventually run out of memory with a non-tail-recursive copylist and a big enough list. Scheme seems to be able to optimise "tail recursion modulo cons" - I've tried copylist with tens of millions of elements and scheme doesn't break; rainbow does.