Wages are going up, so McDonalds is reducing the number of jobs. If you come inside to order, you have to fill your own drink; if you drive through, a robot does it. Stores have ordering kiosks and app based ordering so less staff needs to take orders. They've experimented with call center drive through processing before (it didn't work well at the time). It's harder to see, but they do lots of labor saving in the kitchen too.
The Founder was a nice movie about McDonald's founding. They have automation and labor-saving devices and processes cooked right into their early DNA. Recent efforts around automated ordering are just the last straw in a long line of efficiency optimizations.
