Meanwhile, there are an awful lot of people who just don't like reduce/fold in any situation. The quote "Inside every reduce is a loop trying to get out" appears quite frequently, on this list and elsewhere.
And yet we keep getting cases like the sum discussion which is a fold in essence, but people reject suggestions of "just use a loop". So it doesn't look like the loop is trying very hard to get out :-)
Whether "inside every specialised function there is a fold trying to get out" is any more likely to gain traction, I don't know...