I remember we had this discussion in the earlier days of the wiki on how to format dates across the wiki. Ultimately, the decision that I believe we reached was never really carried out, so I think we should reopen the discussion now that the wiki is more mature, as well as because I doubt anybody remembers the arguments we had back then to support one way or another.
For short-form dates, I would suggest the YYYY-MM-DD format. You see it for example in infoboxes, the date of birth and death for example. This is an international format that not only removes all ambiguity (such as MM-DD or DD-MM) but also makes it easier to order dates on computers if someone ever needs to pull this data.
For longer form dates, I'm not really sure. There's two accepted spellings in English: February 4, 2022 or 4th of February, 2022. The latter is a bit more old-fashioned and out of style, and might confuse some of our readers and writers who might not be 100% fluent in English. For that reason I would suggest the first proposition, i.e. February 4, 2022. In English, months are always Capitalised.
Once we decide on a spelling we'll have fun reformatting the whole wiki 😵💫