I don't think it's silly, rather it just moves the question a bit. As you indicate, the question is merely moved to "which is the better way of expressing a range". It seems that Djikstra prefers "0 <= i < N" to "1<= i < N+1". However, he doesn't say why that's any better. I agree that it looks better, but there's another formulation "0 < i <= N" that looks just as good. Why isn't that just as good? He leaves the question open.
When your only tool is a hammer, all problems look like your thumb.