A burger made of fresh, never frozen ingredients from In N Out or Five Guys only carries a 50-80% markup [1], and those stores are properly staffed and consequently offer a much more pleasant dining room experience.
I suppose my point is that it is possible to deliver a good customer experience and still maintain a healthy operating margin. What McDonald’s is doing to make the whole experience worse is not a necessity to keep the business alive, it is a choice to maximize profits at the expense of the brand’s long-term reputation.