I agree that attempting to have one canonical recipe for something like "Macaroni and Cheese" is futile and counter-productive, but I don't think this project has to end up like that.
For example, if the Macaroni and Cheese Cookbook page turned into an index for dozens of M+C recipes, named for the cultural influence or ingredient influence, that could certainly be useful.
With the current state of recipes on the internet (most are extremely low quality click-bait designed around ad word integration for profit, for example, searching "instant pot recipes" returns just loads and loads of terrible monetized results) a source like this doesn't have to try terribly hard to be a high quality resource
Even so it feels like it would be more useful as an encyclopedia of flavor than it would be for help making dinner tonight. Learning about the evolution of a dish would be very interesting, but I wouldn't trust an anonymous wiki editor very much in terms of actual cooking
I think the biggest problem to me is that recipes are very much driven by personality. People learn a few chefs/sources that have produced good results for them, and they stick to those sources. They go buy the cookbooks from those people and stay in a safe walled garden where they can trust each recipe
I think another big problem is the low quality of the recipe source. Traditionally listing ingredients with some steps along the way is sufficient for the experienced cook, but good modern recipes (to me) do so much more than list ingredients and steps.
I follow a chef J. Kenji Lopez-Alt and when he breaks down a recipe (for Serious Eats or his books like The Food Lab) he goes so much more into WHY each decision was made, which empowers you to not just understand the decision but also change it.
For example: The All-American Beef Stew -(https://www.seriouseats.com/2016/01/food-lab-follow-the-rule...) (and the short version https://www.seriouseats.com/recipes/2016/01/all-american-bee...) Every aspect of the dish is analyzed and discussed!
Or Fuschia Dunlop's translation of Sichuan cooking for a western audience, (e.g. https://andrewzimmern.com/2013/03/28/fuchsia-dunlops-fish-fr...) she helps distill Chinese culture and the cooking of this region with a lot more than an ingredient list and a step. That information, delivered by a trusted expert, is vital to understanding and mastering a dish from a culture very different than my own.
Why would I want some anonymously written/edited list of ingredients and steps when I can have a professionally produced, multi-media (huge useful step by step images AND video), "scientifically-inspired" discussion of the recipe and why it does what it does?
That's the kicker for me, I'll always go back to Kenji or Alton or Fuschia or someone I trust because I know they have delivered good results and researched the recipe deeply enough to help me succeed not just at their version but at my own version too