If it really bothers you that much... open up the diy_glossary.txt file.
1. Change the recipe requirements to show "Tying equipment" instead of "Rope".
Change {Rope} in these recipes to {Tying equipment}.
or
2. Modify the recipes so they only accept rope or leather rope.
Change {Rope} to {*rope}.
The vanilla .txt files get automatically regenerated when you launch the game, so you'll probably have to do this every single time you start it up. (Not 100% sure on that; I know for a fact missing files reappear, but I'm not sure about modified ones.) It seems like way too much trouble IMO for something that has literally no effect on gameplay, but, hey, if you want a fix, there's your fix.
Alternatively, you could try creating a separate diy mod file for these recipes, but I don't know what happens if you try to override base items in a mod. Personally, I'd say just leave it be.