This comes under the category of not worrying about things beyond your control. Your only job is to craft the best application you can. If you can do that by the early deadline, and you are certain Yale is your first choice and you are certain you can afford to attend if accepted, then go for it. Otherwise apply RD.
There are students who defer every year. Even pre-pandemic a handful of kids each round would take a gap year. The pandemic is far from over. The beginning of next school year might be as messy as the beginning of this school year. You can’t control that.
Yale is going to accept more students than they have room for anyway because no college has a 100% yield. If they have an unusual number of deferrals now returning to campus, it could just as easily mean no one from the waitlist gets in rather than fewer acceptance letters going out.