Comment by shiomiru

I don't think that's related? The bug alluded to looks something like

    function rm(node) {
        for (const child of ls(node))
            rm(child);
        unlink(node);
    }

and no amount of tail call optimization will save you here, because this isn't tail recursion. Of course you could rewrite it using an explicit stack + tail recursion, but then you might as well be using a while loop.